81902507 has 2 divisors, whose sum is σ = 81902508. Its totient is φ = 81902506.

The previous prime is 81902479. The next prime is 81902533. The reversal of 81902507 is 70520918.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 81902507 - 2⁸ = 81902251 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (81902567) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40951253 + 40951254.

It is an arithmetic number, because the mean of its divisors is an integer number (40951254).

Almost surely, 2^81902507 is an apocalyptic number.

81902507 is a deficient number, since it is larger than the sum of its proper divisors (1).

81902507 is an equidigital number, since it uses as much as digits as its factorization.

81902507 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5040, while the sum is 32.

The square root of 81902507 is about 9050.0003867403. Note that the first 3 decimals coincide. The cubic root of 81902507 is about 434.2759028430.

The spelling of 81902507 in words is "eighty-one million, nine hundred two thousand, five hundred seven".