120111981 has 12 divisors (see below), whose sum is σ = 176032416. Its totient is φ = 72794920.

The previous prime is 120111973. The next prime is 120111983. The reversal of 120111981 is 189111021.

It is not a de Polignac number, because 120111981 - 2³ = 120111973 is a prime.

It is a super-2 number, since 2×120111981² = 28853775959488722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (120111983) 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, 165081 + ... + 165806.

It is an arithmetic number, because the mean of its divisors is an integer number (14669368).

Almost surely, 2^120111981 is an apocalyptic number.

120111981 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

120111981 is a deficient number, since it is larger than the sum of its proper divisors (55920435).

120111981 is a wasteful number, since it uses less digits than its factorization.

120111981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 330912 (or 330901 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 24.

The square root of 120111981 is about 10959.5611682220. The cubic root of 120111981 is about 493.3957943295.

It can be divided in two parts, 120 and 111981, that added together give a triangular number (112101 = T₄₇₃).

The spelling of 120111981 in words is "one hundred twenty million, one hundred eleven thousand, nine hundred eighty-one".