20402724816 has 240 divisors, whose sum is σ = 62022744576. Its totient is φ = 6244153344.

The previous prime is 20402724787. The next prime is 20402724817. The reversal of 20402724816 is 61842720402.

20402724816 is a `hidden beast` number, since 2 + 0 + 402 + 7 + 248 + 1 + 6 = 666.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20402724817) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 8248956 + ... + 8251428.

Almost surely, 2^20402724816 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20402724816, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31011372288).

20402724816 is an abundant number, since it is smaller than the sum of its proper divisors (41620019760).

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

20402724816 is a wasteful number, since it uses less digits than its factorization.

20402724816 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2610 (or 2601 counting only the distinct ones).

The product of its (nonzero) digits is 43008, while the sum is 36.

The spelling of 20402724816 in words is "twenty billion, four hundred two million, seven hundred twenty-four thousand, eight hundred sixteen".