9891551372 has 12 divisors (see below), whose sum is σ = 17313709896. Its totient is φ = 4944777120.

The previous prime is 9891551363. The next prime is 9891551381. The reversal of 9891551372 is 2731551989.

It is an interprime number because it is at equal distance from previous prime (9891551363) and next prime (9891551381).

It is a self number, because there is not a number n which added to its sum of digits gives 9891551372.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 227129 + ... + 267152.

It is an arithmetic number, because the mean of its divisors is an integer number (1442809158).

Almost surely, 2^9891551372 is an apocalyptic number.

It is an amenable number.

9891551372 is a deficient number, since it is larger than the sum of its proper divisors (7422158524).

9891551372 is a wasteful number, since it uses less digits than its factorization.

9891551372 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 499288 (or 499286 counting only the distinct ones).

The product of its digits is 680400, while the sum is 50.

The square root of 9891551372 is about 99456.2786957163. The cubic root of 9891551372 is about 2146.6181823705.

The spelling of 9891551372 in words is "nine billion, eight hundred ninety-one million, five hundred fifty-one thousand, three hundred seventy-two".