9951990 has 32 divisors (see below), whose sum is σ = 24019200. Its totient is φ = 2638944.

The previous prime is 9951973. The next prime is 9952037. The reversal of 9951990 is 991599.

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, 5137 + ... + 6803.

It is an arithmetic number, because the mean of its divisors is an integer number (750600).

Almost surely, 2^9951990 is an apocalyptic number.

9951990 is an abundant number, since it is smaller than the sum of its proper divisors (14067210).

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

9951990 is a wasteful number, since it uses less digits than its factorization.

9951990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1876.

The product of its (nonzero) digits is 32805, while the sum is 42.

The square root of 9951990 is about 3154.6774795532. The cubic root of 9951990 is about 215.0981343968.

The spelling of 9951990 in words is "nine million, nine hundred fifty-one thousand, nine hundred ninety".