981090251 has 4 divisors (see below), whose sum is σ = 1032726600. Its totient is φ = 929453904.

The previous prime is 981090223. The next prime is 981090259. The reversal of 981090251 is 152090189.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-981090251 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (981090259) 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, 25818146 + ... + 25818183.

It is an arithmetic number, because the mean of its divisors is an integer number (258181650).

Almost surely, 2^981090251 is an apocalyptic number.

981090251 is a deficient number, since it is larger than the sum of its proper divisors (51636349).

981090251 is a wasteful number, since it uses less digits than its factorization.

981090251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51636348.

The product of its (nonzero) digits is 6480, while the sum is 35.

The square root of 981090251 is about 31322.3602399308. The cubic root of 981090251 is about 993.6565966509.

The spelling of 981090251 in words is "nine hundred eighty-one million, ninety thousand, two hundred fifty-one".