249047681 has 2 divisors, whose sum is σ = 249047682. Its totient is φ = 249047680.

The previous prime is 249047647. The next prime is 249047693. The reversal of 249047681 is 186740942.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 168766081 + 80281600 = 12991^2 + 8960^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-249047681 is a prime.

It is a super-2 number, since 2×249047681² = 124049494822955522, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (249047581) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 124523840 + 124523841.

It is an arithmetic number, because the mean of its divisors is an integer number (124523841).

Almost surely, 2^249047681 is an apocalyptic number.

It is an amenable number.

249047681 is a deficient number, since it is larger than the sum of its proper divisors (1).

249047681 is an equidigital number, since it uses as much as digits as its factorization.

249047681 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96768, while the sum is 41.

The square root of 249047681 is about 15781.2445960387. The cubic root of 249047681 is about 629.1596092791.

The spelling of 249047681 in words is "two hundred forty-nine million, forty-seven thousand, six hundred eighty-one".