20400464457 has 24 divisors (see below), whose sum is σ = 31283123040. Its totient is φ = 12766481280.

The previous prime is 20400464443. The next prime is 20400464459. The reversal of 20400464457 is 75446400402.

20400464457 is a `hidden beast` number, since 2 + 0 + 4 + 0 + 0 + 4 + 644 + 5 + 7 = 666.

It is not a de Polignac number, because 20400464457 - 2⁶ = 20400464393 is a prime.

It is a super-2 number, since 2×20400464457² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (20400464459) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 117919 + ... + 233892.

It is an arithmetic number, because the mean of its divisors is an integer number (1303463460).

Almost surely, 2^20400464457 is an apocalyptic number.

It is an amenable number.

20400464457 is a deficient number, since it is larger than the sum of its proper divisors (10882658583).

20400464457 is a wasteful number, since it uses less digits than its factorization.

20400464457 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 352213 (or 352210 counting only the distinct ones).

The product of its (nonzero) digits is 107520, while the sum is 36.

Adding to 20400464457 its reverse (75446400402), we get a palindrome (95846864859).

The spelling of 20400464457 in words is "twenty billion, four hundred million, four hundred sixty-four thousand, four hundred fifty-seven".