981149251 has 2 divisors, whose sum is σ = 981149252. Its totient is φ = 981149250.

The previous prime is 981149243. The next prime is 981149297. The reversal of 981149251 is 152941189.

It is a weak prime.

It is an emirp because it is prime and its reverse (152941189) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 981149251 - 2³ = 981149243 is a prime.

It is a super-2 number, since 2×981149251² = 1925307705475722002, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (981149231) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 490574625 + 490574626.

It is an arithmetic number, because the mean of its divisors is an integer number (490574626).

Almost surely, 2^981149251 is an apocalyptic number.

981149251 is a deficient number, since it is larger than the sum of its proper divisors (1).

981149251 is an equidigital number, since it uses as much as digits as its factorization.

981149251 is an evil number, because the sum of its binary digits is even.

The product of its digits is 25920, while the sum is 40.

The square root of 981149251 is about 31323.3020449633. The cubic root of 981149251 is about 993.6765148198.

The spelling of 981149251 in words is "nine hundred eighty-one million, one hundred forty-nine thousand, two hundred fifty-one".