991976 has 8 divisors (see below), whose sum is σ = 1859970. Its totient is φ = 495984.

The previous prime is 991973. The next prime is 991979. The reversal of 991976 is 679199.

It is a happy number.

991976 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (991973) and next prime (991979).

It can be written as a sum of positive squares in only one way, i.e., 940900 + 51076 = 970^2 + 226^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 991976.

It is not an unprimeable number, because it can be changed into a prime (991973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 61991 + ... + 62006.

2⁹⁹¹⁹⁷⁶ is an apocalyptic number.

It is an amenable number.

991976 is a deficient number, since it is larger than the sum of its proper divisors (867994).

991976 is a wasteful number, since it uses less digits than its factorization.

991976 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 124003 (or 123999 counting only the distinct ones).

The product of its digits is 30618, while the sum is 41.

The square root of 991976 is about 995.9799194763. The cubic root of 991976 is about 99.7318147430.

The spelling of 991976 in words is "nine hundred ninety-one thousand, nine hundred seventy-six".