187120981 has 4 divisors (see below), whose sum is σ = 188100864. Its totient is φ = 186141100.

The previous prime is 187120961. The next prime is 187121003. The reversal of 187120981 is 189021781.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 187120981 - 2¹³ = 187112789 is a prime.

It is a super-2 number, since 2×187120981² = 70028523060804722, which 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 187120981.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (187120961) 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, 489655 + ... + 490036.

It is an arithmetic number, because the mean of its divisors is an integer number (47025216).

Almost surely, 2^187120981 is an apocalyptic number.

It is an amenable number.

187120981 is a deficient number, since it is larger than the sum of its proper divisors (979883).

187120981 is an equidigital number, since it uses as much as digits as its factorization.

187120981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 979882.

The product of its (nonzero) digits is 8064, while the sum is 37.

The square root of 187120981 is about 13679.2171194115. The cubic root of 187120981 is about 571.9712002795.

The spelling of 187120981 in words is "one hundred eighty-seven million, one hundred twenty thousand, nine hundred eighty-one".