21317567040 has 840 divisors, whose sum is σ = 95356046016. Its totient is φ = 4425062400.

The previous prime is 21317567021. The next prime is 21317567041. The reversal of 21317567040 is 4076571312.

It is a happy number.

21317567040 is a `hidden beast` number, since 21 + 31 + 7 + 567 + 0 + 40 = 666.

It is a tau number, because it is divible by the number of its divisors (840).

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

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 = 21317566986 and 21317567004.

It is not an unprimeable number, because it can be changed into a prime (21317567041) by changing a digit.

It is a polite number, since it can be written in 119 ways as a sum of consecutive naturals, for example, 21953755 + ... + 21954725.

Almost surely, 2^21317567040 is an apocalyptic number.

21317567040 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 21317567040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47678023008).

21317567040 is an abundant number, since it is smaller than the sum of its proper divisors (74038478976).

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

21317567040 is a wasteful number, since it uses less digits than its factorization.

21317567040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1029 (or 999 counting only the distinct ones).

The product of its (nonzero) digits is 35280, while the sum is 36.

The spelling of 21317567040 in words is "twenty-one billion, three hundred seventeen million, five hundred sixty-seven thousand, forty".