30721417640 has 16 divisors (see below), whose sum is σ = 69123189780. Its totient is φ = 12288567040.

The previous prime is 30721417637. The next prime is 30721417651. The reversal of 30721417640 is 4671412703.

It can be written as a sum of positive squares in 2 ways, for example, as 30708356644 + 13060996 = 175238^2 + 3614^2 .

It is a super-2 number, since 2×30721417640² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 30721417640.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 384017681 + ... + 384017760.

Almost surely, 2^30721417640 is an apocalyptic number.

It is an amenable number.

30721417640 is an abundant number, since it is smaller than the sum of its proper divisors (38401772140).

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

30721417640 is a wasteful number, since it uses less digits than its factorization.

30721417640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 768035452 (or 768035448 counting only the distinct ones).

The product of its (nonzero) digits is 28224, while the sum is 35.

The spelling of 30721417640 in words is "thirty billion, seven hundred twenty-one million, four hundred seventeen thousand, six hundred forty".