21930919382831 has 16 divisors (see below), whose sum is σ = 23603541115968. Its totient is φ = 20300859532800.

The previous prime is 21930919382737. The next prime is 21930919382843. The reversal of 21930919382831 is 13828391903912.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 21930919382831 - 2³⁴ = 21913739513647 is a prime.

It is a super-2 number, since 2×21930919382831² (a number of 27 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (59) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21930919882831) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12161846 + ... + 13848188.

It is an arithmetic number, because the mean of its divisors is an integer number (1475221319748).

Almost surely, 2^{21930919382831} is an apocalyptic number.

21930919382831 is a deficient number, since it is larger than the sum of its proper divisors (1672621733137).

21930919382831 is a wasteful number, since it uses less digits than its factorization.

21930919382831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1698962.

The product of its (nonzero) digits is 5038848, while the sum is 59.

The spelling of 21930919382831 in words is "twenty-one trillion, nine hundred thirty billion, nine hundred nineteen million, three hundred eighty-two thousand, eight hundred thirty-one".