991901892 has 24 divisors (see below), whose sum is σ = 2320108000. Its totient is φ = 329823936.

The previous prime is 991901861. The next prime is 991901893. The reversal of 991901892 is 298109199.

It is not an unprimeable number, because it can be changed into a prime (991901893) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 96142 + ... + 105957.

Almost surely, 2^991901892 is an apocalyptic number.

It is an amenable number.

991901892 is an abundant number, since it is smaller than the sum of its proper divisors (1328206108).

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

991901892 is a wasteful number, since it uses less digits than its factorization.

991901892 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 202515 (or 202513 counting only the distinct ones).

The product of its (nonzero) digits is 104976, while the sum is 48.

The square root of 991901892 is about 31494.4739914798. The cubic root of 991901892 is about 997.2933111118.

The spelling of 991901892 in words is "nine hundred ninety-one million, nine hundred one thousand, eight hundred ninety-two".