21716051658 has 32 divisors (see below), whose sum is σ = 50377542144. Its totient is φ = 6111979632.

The previous prime is 21716051641. The next prime is 21716051663. The reversal of 21716051658 is 85615061712.

It is a super-2 number, since 2×21716051658² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3855760 + ... + 3861387.

It is an arithmetic number, because the mean of its divisors is an integer number (1574298192).

Almost surely, 2^21716051658 is an apocalyptic number.

21716051658 is an abundant number, since it is smaller than the sum of its proper divisors (28661490486).

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

21716051658 is a wasteful number, since it uses less digits than its factorization.

21716051658 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7717226.

The product of its (nonzero) digits is 100800, while the sum is 42.

The spelling of 21716051658 in words is "twenty-one billion, seven hundred sixteen million, fifty-one thousand, six hundred fifty-eight".