120157981 has 4 divisors (see below), whose sum is σ = 123405532. Its totient is φ = 116910432.

The previous prime is 120157969. The next prime is 120157987. The reversal of 120157981 is 189751021.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 189751021 = 59 ⋅3216119.

It can be written as a sum of positive squares in 2 ways, for example, as 96236100 + 23921881 = 9810^2 + 4891^2 .

It is a cyclic number.

It is not a de Polignac number, because 120157981 - 2⁵ = 120157949 is a prime.

It is a super-2 number, since 2×120157981² = 28875880795992722, which 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 (120157987) 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, 1623720 + ... + 1623793.

It is an arithmetic number, because the mean of its divisors is an integer number (30851383).

Almost surely, 2^120157981 is an apocalyptic number.

It is an amenable number.

120157981 is a deficient number, since it is larger than the sum of its proper divisors (3247551).

120157981 is an equidigital number, since it uses as much as digits as its factorization.

120157981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3247550.

The product of its (nonzero) digits is 5040, while the sum is 34.

The square root of 120157981 is about 10961.6595915035. The cubic root of 120157981 is about 493.4587725315.

The spelling of 120157981 in words is "one hundred twenty million, one hundred fifty-seven thousand, nine hundred eighty-one".