91042199824 has 45 divisors (see below), whose sum is σ = 177696941679. Its totient is φ = 45187384320.

The previous prime is 91042199797. The next prime is 91042199827. The reversal of 91042199824 is 42899124019.

The square root of 91042199824 is 301732.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 16604899600 + 74437300224 = 128860^2 + 272832^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91042199827) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 290869492 + ... + 290869804.

Almost surely, 2^91042199824 is an apocalyptic number.

91042199824 is the 301732-nd square number.

It is an amenable number.

91042199824 is a deficient number, since it is larger than the sum of its proper divisors (86654741855).

91042199824 is an frugal number, since it uses more digits than its factorization.

91042199824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1116 (or 556 counting only the distinct ones).

The product of its (nonzero) digits is 373248, while the sum is 49.

Multiplying 91042199824 by its sum of digits (49), we get a square (4461067791376 = 2112124²).

The spelling of 91042199824 in words is "ninety-one billion, forty-two million, one hundred ninety-nine thousand, eight hundred twenty-four".