81097750 has 16 divisors (see below), whose sum is σ = 151815456. Its totient is φ = 32439000.

The previous prime is 81097733. The next prime is 81097799. The reversal of 81097750 is 5779018.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 161946 + ... + 162445.

It is an arithmetic number, because the mean of its divisors is an integer number (9488466).

Almost surely, 2^81097750 is an apocalyptic number.

81097750 is a deficient number, since it is larger than the sum of its proper divisors (70717706).

81097750 is a wasteful number, since it uses less digits than its factorization.

81097750 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 324408 (or 324398 counting only the distinct ones).

The product of its (nonzero) digits is 17640, while the sum is 37.

The square root of 81097750 is about 9005.4289181582. The cubic root of 81097750 is about 432.8488503792.

The spelling of 81097750 in words is "eighty-one million, ninety-seven thousand, seven hundred fifty".