81752398 has 48 divisors (see below), whose sum is σ = 153632160. Its totient is φ = 31943808.

The previous prime is 81752381. The next prime is 81752399. The reversal of 81752398 is 89325718.

Its product of digits (120960) is a multiple of the sum of its prime divisors (448).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81752399) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 257736 + ... + 258052.

It is an arithmetic number, because the mean of its divisors is an integer number (3200670).

Almost surely, 2^81752398 is an apocalyptic number.

81752398 is a deficient number, since it is larger than the sum of its proper divisors (71879762).

81752398 is a wasteful number, since it uses less digits than its factorization.

81752398 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 461 (or 448 counting only the distinct ones).

The product of its digits is 120960, while the sum is 43.

The square root of 81752398 is about 9041.7032687431. The cubic root of 81752398 is about 434.0104303524.

The spelling of 81752398 in words is "eighty-one million, seven hundred fifty-two thousand, three hundred ninety-eight".