91431850129 has 9 divisors (see below), whose sum is σ = 92974060881. Its totient is φ = 89914824720.

The previous prime is 91431850123. The next prime is 91431850229. The reversal of 91431850129 is 92105813419.

The square root of 91431850129 is 302377.

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 4317147025 + 87114703104 = 65705^2 + 295152^2 .

It is not a de Polignac number, because 91431850129 - 2²¹ = 91429752977 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91431850123) 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, 18442519 + ... + 18447475.

It is an arithmetic number, because the mean of its divisors is an integer number (10330451209).

Almost surely, 2^91431850129 is an apocalyptic number.

91431850129 is the 302377-th square number.

91431850129 is the 151189-th centered octagonal number.

It is an amenable number.

91431850129 is a deficient number, since it is larger than the sum of its proper divisors (1542210752).

91431850129 is an frugal number, since it uses more digits than its factorization.

91431850129 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10036 (or 5018 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 43.

The spelling of 91431850129 in words is "ninety-one billion, four hundred thirty-one million, eight hundred fifty thousand, one hundred twenty-nine".