21016549730658 has 64 divisors (see below), whose sum is σ = 44889709593600. Its totient is φ = 6545094420480.

The previous prime is 21016549730653. The next prime is 21016549730681. The reversal of 21016549730658 is 85603794561012.

It is a super-2 number, since 2×21016549730658² (a number of 27 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21016549730598 and 21016549730607.

It is not an unprimeable number, because it can be changed into a prime (21016549730653) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 54660010 + ... + 55043162.

It is an arithmetic number, because the mean of its divisors is an integer number (701401712400).

It is a 1-persistent number, because it is pandigital, but 2⋅21016549730658 = 42033099461316 is not.

Almost surely, 2^{21016549730658} is an apocalyptic number.

21016549730658 is an abundant number, since it is smaller than the sum of its proper divisors (23873159862942).

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

21016549730658 is a wasteful number, since it uses less digits than its factorization.

21016549730658 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 393387.

The product of its (nonzero) digits is 10886400, while the sum is 57.

The spelling of 21016549730658 in words is "twenty-one trillion, sixteen billion, five hundred forty-nine million, seven hundred thirty thousand, six hundred fifty-eight".