21697124766 has 16 divisors (see below), whose sum is σ = 43497820800. Its totient is φ = 7215113048.

The previous prime is 21697124759. The next prime is 21697124767. The reversal of 21697124766 is 66742179612.

It is a happy number.

It is a super-2 number, since 2×21697124766² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21697124767) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4312746 + ... + 4317773.

It is an arithmetic number, because the mean of its divisors is an integer number (2718613800).

Almost surely, 2^21697124766 is an apocalyptic number.

21697124766 is an abundant number, since it is smaller than the sum of its proper divisors (21800696034).

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

21697124766 is a wasteful number, since it uses less digits than its factorization.

21697124766 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8630943.

The product of its digits is 1524096, while the sum is 51.

The spelling of 21697124766 in words is "twenty-one billion, six hundred ninety-seven million, one hundred twenty-four thousand, seven hundred sixty-six".