91290402 has 120 divisors (see below), whose sum is σ = 247838976. Its totient is φ = 24599376.

The previous prime is 91290401. The next prime is 91290413. The reversal of 91290402 is 20409219.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (91290401) by changing a digit.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 409263 + ... + 409485.

Almost surely, 2^91290402 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91290402, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (123919488).

91290402 is an abundant number, since it is smaller than the sum of its proper divisors (156548574).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91290402 is a wasteful number, since it uses less digits than its factorization.

91290402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 282 (or 254 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 27.

The square root of 91290402 is about 9554.6010905741. The cubic root of 91290402 is about 450.2721021012.

The spelling of 91290402 in words is "ninety-one million, two hundred ninety thousand, four hundred two".