991015068 has 48 divisors (see below), whose sum is σ = 2527386624. Its totient is φ = 300875520.

The previous prime is 991015021. The next prime is 991015073. The reversal of 991015068 is 860510199.

It is a super-2 number, since 2×991015068² = 1964221730006089248, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 72030 + ... + 84677.

It is an arithmetic number, because the mean of its divisors is an integer number (52653888).

Almost surely, 2^991015068 is an apocalyptic number.

It is an amenable number.

991015068 is an abundant number, since it is smaller than the sum of its proper divisors (1536371556).

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

991015068 is a wasteful number, since it uses less digits than its factorization.

991015068 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156762 (or 156760 counting only the distinct ones).

The product of its (nonzero) digits is 19440, while the sum is 39.

The square root of 991015068 is about 31480.3918018820. The cubic root of 991015068 is about 996.9960077331.

The spelling of 991015068 in words is "nine hundred ninety-one million, fifteen thousand, sixty-eight".