7991901 has 6 divisors (see below), whose sum is σ = 11543870. Its totient is φ = 5327928.

The previous prime is 7991897. The next prime is 7991939. The reversal of 7991901 is 1091997.

It can be written as a sum of positive squares in only one way, i.e., 7986276 + 5625 = 2826^2 + 75^2 .

It is not a de Polignac number, because 7991901 - 2² = 7991897 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7991941) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 443986 + ... + 444003.

Almost surely, 2^7991901 is an apocalyptic number.

It is an amenable number.

7991901 is a deficient number, since it is larger than the sum of its proper divisors (3551969).

7991901 is a wasteful number, since it uses less digits than its factorization.

7991901 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 887995 (or 887992 counting only the distinct ones).

The product of its (nonzero) digits is 5103, while the sum is 36.

The square root of 7991901 is about 2826.9950477495. The cubic root of 7991901 is about 199.9324855449.

The spelling of 7991901 in words is "seven million, nine hundred ninety-one thousand, nine hundred one".