21801119931 has 6 divisors (see below), whose sum is σ = 31490506580. Its totient is φ = 14534079948.

The previous prime is 21801119929. The next prime is 21801119939. The reversal of 21801119931 is 13991110812.

It is not a de Polignac number, because 21801119931 - 2¹ = 21801119929 is a prime.

It is a super-2 number, since 2×21801119931² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21801119939) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1211173321 + ... + 1211173338.

Almost surely, 2^21801119931 is an apocalyptic number.

21801119931 is a deficient number, since it is larger than the sum of its proper divisors (9689386649).

21801119931 is a wasteful number, since it uses less digits than its factorization.

21801119931 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2422346665 (or 2422346662 counting only the distinct ones).

The product of its (nonzero) digits is 3888, while the sum is 36.

The spelling of 21801119931 in words is "twenty-one billion, eight hundred one million, one hundred nineteen thousand, nine hundred thirty-one".