15111109981 has 16 divisors (see below), whose sum is σ = 16678327680. Its totient is φ = 13576837120.

The previous prime is 15111109973. The next prime is 15111109987. The reversal of 15111109981 is 18990111151.

It is not a de Polignac number, because 15111109981 - 2³ = 15111109973 is a prime.

It is a super-2 number, since 2×15111109981² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 15111109981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15111109987) 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, 421560 + ... + 455998.

It is an arithmetic number, because the mean of its divisors is an integer number (1042395480).

Almost surely, 2^15111109981 is an apocalyptic number.

15111109981 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

15111109981 is a deficient number, since it is larger than the sum of its proper divisors (1567217699).

15111109981 is a wasteful number, since it uses less digits than its factorization.

15111109981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34916.

The product of its (nonzero) digits is 3240, while the sum is 37.

The spelling of 15111109981 in words is "fifteen billion, one hundred eleven million, one hundred nine thousand, nine hundred eighty-one".