18931400413981 has 12 divisors (see below), whose sum is σ = 20809283740000. Its totient is φ = 17210042225640.

The previous prime is 18931400413979. The next prime is 18931400413997.

18931400413981 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 18931400413981 - 2¹ = 18931400413979 is a prime.

It is a super-2 number, since 2×18931400413981² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18931400413921) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5158960 + ... + 8029798.

Almost surely, 2^{18931400413981} is an apocalyptic number.

18931400413981 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

18931400413981 is a deficient number, since it is larger than the sum of its proper divisors (1877883326019).

18931400413981 is a wasteful number, since it uses less digits than its factorization.

18931400413981 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2925360 (or 2925349 counting only the distinct ones).

The product of its (nonzero) digits is 746496, while the sum is 52.

The spelling of 18931400413981 in words is "eighteen trillion, nine hundred thirty-one billion, four hundred million, four hundred thirteen thousand, nine hundred eighty-one".