120928991 has 4 divisors (see below), whose sum is σ = 120989184. Its totient is φ = 120868800.

The previous prime is 120928961. The next prime is 120929033. The reversal of 120928991 is 199829021.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 120928991 - 2²² = 116734687 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (120928931) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26975 + ... + 31136.

It is an arithmetic number, because the mean of its divisors is an integer number (30247296).

Almost surely, 2^120928991 is an apocalyptic number.

120928991 is a deficient number, since it is larger than the sum of its proper divisors (60193).

120928991 is an equidigital number, since it uses as much as digits as its factorization.

120928991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60192.

The product of its (nonzero) digits is 23328, while the sum is 41.

The square root of 120928991 is about 10996.7718445005. The cubic root of 120928991 is about 494.5119714737.

The spelling of 120928991 in words is "one hundred twenty million, nine hundred twenty-eight thousand, nine hundred ninety-one".