91551906 has 24 divisors (see below), whose sum is σ = 198691740. Its totient is φ = 30466656.

The previous prime is 91551883. The next prime is 91551907. The reversal of 91551906 is 60915519.

It can be written as a sum of positive squares in 2 ways, for example, as 90725625 + 826281 = 9525^2 + 909^2 .

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (91551907) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 7860 + ... + 15648.

Almost surely, 2^91551906 is an apocalyptic number.

91551906 is an abundant number, since it is smaller than the sum of its proper divisors (107139834).

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

91551906 is a wasteful number, since it uses less digits than its factorization.

91551906 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8450 (or 8447 counting only the distinct ones).

The product of its (nonzero) digits is 12150, while the sum is 36.

The square root of 91551906 is about 9568.2760202661. The cubic root of 91551906 is about 450.7016313871.

The spelling of 91551906 in words is "ninety-one million, five hundred fifty-one thousand, nine hundred six".