87249439 has 2 divisors, whose sum is σ = 87249440. Its totient is φ = 87249438.

The previous prime is 87249431. The next prime is 87249443. The reversal of 87249439 is 93494278.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 87249439 - 2³ = 87249431 is a prime.

It is a super-2 number, since 2×87249439² = 15224929211629442, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (87249431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 43624719 + 43624720.

It is an arithmetic number, because the mean of its divisors is an integer number (43624720).

Almost surely, 2^87249439 is an apocalyptic number.

87249439 is a deficient number, since it is larger than the sum of its proper divisors (1).

87249439 is an equidigital number, since it uses as much as digits as its factorization.

87249439 is an evil number, because the sum of its binary digits is even.

The product of its digits is 435456, while the sum is 46.

The square root of 87249439 is about 9340.7408164449. The cubic root of 87249439 is about 443.5278355215.

The spelling of 87249439 in words is "eighty-seven million, two hundred forty-nine thousand, four hundred thirty-nine".