249556081 has 2 divisors, whose sum is σ = 249556082. Its totient is φ = 249556080.

The previous prime is 249556061. The next prime is 249556117. The reversal of 249556081 is 180655942.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 248346081 + 1210000 = 15759^2 + 1100^2 .

It is a cyclic number.

It is not a de Polignac number, because 249556081 - 2⁷ = 249555953 is a prime.

It is a super-2 number, since 2×249556081² = 124556475128157122, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (249556061) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 124778040 + 124778041.

It is an arithmetic number, because the mean of its divisors is an integer number (124778041).

Almost surely, 2^249556081 is an apocalyptic number.

It is an amenable number.

249556081 is a deficient number, since it is larger than the sum of its proper divisors (1).

249556081 is an equidigital number, since it uses as much as digits as its factorization.

249556081 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 86400, while the sum is 40.

The square root of 249556081 is about 15797.3441122234. The cubic root of 249556081 is about 629.5874354365.

The spelling of 249556081 in words is "two hundred forty-nine million, five hundred fifty-six thousand, eighty-one".