20500440 has 32 divisors (see below), whose sum is σ = 61501680. Its totient is φ = 5466752.

The previous prime is 20500439. The next prime is 20500457. The reversal of 20500440 is 4400502.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 85299 + ... + 85538.

Almost surely, 2^20500440 is an apocalyptic number.

20500440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20500440 is an abundant number, since it is smaller than the sum of its proper divisors (41001240).

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

20500440 is a wasteful number, since it uses less digits than its factorization.

20500440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 170851 (or 170847 counting only the distinct ones).

The product of its (nonzero) digits is 160, while the sum is 15.

The square root of 20500440 is about 4527.7411586795. The cubic root of 20500440 is about 273.6871417988.

Adding to 20500440 its reverse (4400502), we get a palindrome (24900942).

The spelling of 20500440 in words is "twenty million, five hundred thousand, four hundred forty".