20520442400 has 36 divisors (see below), whose sum is σ = 50095531962. Its totient is φ = 8208176640.

The previous prime is 20520442363. The next prime is 20520442403. The reversal of 20520442400 is 424402502.

It can be written as a sum of positive squares in 3 ways, for example, as 13520108176 + 7000334224 = 116276^2 + 83668^2 .

It is not an unprimeable number, because it can be changed into a prime (20520442403) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 12824477 + ... + 12826076.

Almost surely, 2^20520442400 is an apocalyptic number.

20520442400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20520442400 is an abundant number, since it is smaller than the sum of its proper divisors (29575089562).

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

20520442400 is a wasteful number, since it uses less digits than its factorization.

20520442400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25650573 (or 25650560 counting only the distinct ones).

The product of its (nonzero) digits is 2560, while the sum is 23.

Adding to 20520442400 its reverse (424402502), we get a palindrome (20944844902).

The spelling of 20520442400 in words is "twenty billion, five hundred twenty million, four hundred forty-two thousand, four hundred".