20529617640 has 64 divisors (see below), whose sum is σ = 70387263360. Its totient is φ = 4692483840.

The previous prime is 20529617609. The next prime is 20529617657. The reversal of 20529617640 is 4671692502.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is a junction number, because it is equal to n+sod(n) for n = 20529617592 and 20529617601.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12219171 + ... + 12220850.

It is an arithmetic number, because the mean of its divisors is an integer number (1099800990).

Almost surely, 2^20529617640 is an apocalyptic number.

20529617640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20529617640 is an abundant number, since it is smaller than the sum of its proper divisors (49857645720).

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

20529617640 is a wasteful number, since it uses less digits than its factorization.

20529617640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24440042 (or 24440038 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 42.

The spelling of 20529617640 in words is "twenty billion, five hundred twenty-nine million, six hundred seventeen thousand, six hundred forty".