20587708440 has 576 divisors, whose sum is σ = 76545181440. Its totient is φ = 4973529600.

The previous prime is 20587708433. The next prime is 20587708483. The reversal of 20587708440 is 4480778502.

20587708440 is a `hidden beast` number, since 20 + 587 + 7 + 0 + 8 + 4 + 40 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 143 ways as a sum of consecutive naturals, for example, 136342365 + ... + 136342515.

It is an arithmetic number, because the mean of its divisors is an integer number (132890940).

Almost surely, 2^20587708440 is an apocalyptic number.

20587708440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20587708440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38272590720).

20587708440 is an abundant number, since it is smaller than the sum of its proper divisors (55957473000).

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

20587708440 is a wasteful number, since it uses less digits than its factorization.

20587708440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 286 (or 257 counting only the distinct ones).

The product of its (nonzero) digits is 501760, while the sum is 45.

The spelling of 20587708440 in words is "twenty billion, five hundred eighty-seven million, seven hundred eight thousand, four hundred forty".