20645824140 has 72 divisors (see below), whose sum is σ = 62940477600. Its totient is φ = 5477877504.

The previous prime is 20645824117. The next prime is 20645824153. The reversal of 20645824140 is 4142854602.

20645824140 is a `hidden beast` number, since 2 + 0 + 64 + 582 + 4 + 14 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 20645824095 and 20645824104.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 252369 + ... + 324008.

It is an arithmetic number, because the mean of its divisors is an integer number (874173300).

Almost surely, 2^20645824140 is an apocalyptic number.

20645824140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20645824140 is an abundant number, since it is smaller than the sum of its proper divisors (42294653460).

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

20645824140 is a wasteful number, since it uses less digits than its factorization.

20645824140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 576591 (or 576586 counting only the distinct ones).

The product of its (nonzero) digits is 61440, while the sum is 36.

The spelling of 20645824140 in words is "twenty billion, six hundred forty-five million, eight hundred twenty-four thousand, one hundred forty".