20525403240 has 224 divisors, whose sum is σ = 69451187400. Its totient is φ = 5456885760.

The previous prime is 20525403233. The next prime is 20525403247. The reversal of 20525403240 is 4230452502.

It is a happy number.

20525403240 is a `hidden beast` number, since 2 + 0 + 52 + 540 + 32 + 40 = 666.

It is an interprime number because it is at equal distance from previous prime (20525403233) and next prime (20525403247).

It can be written as a sum of positive squares in 4 ways, for example, as 20338752996 + 186650244 = 142614^2 + 13662^2 .

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20525403247) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 11925580 + ... + 11927300.

Almost surely, 2^20525403240 is an apocalyptic number.

20525403240 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20525403240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34725593700).

20525403240 is an abundant number, since it is smaller than the sum of its proper divisors (48925784160).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20525403240 is a wasteful number, since it uses less digits than its factorization.

20525403240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2159 (or 2140 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 27.

Adding to 20525403240 its reverse (4230452502), we get a palindrome (24755855742).

The spelling of 20525403240 in words is "twenty billion, five hundred twenty-five million, four hundred three thousand, two hundred forty".