974287991 has 2 divisors, whose sum is σ = 974287992. Its totient is φ = 974287990.

The previous prime is 974287987. The next prime is 974288009. The reversal of 974287991 is 199782479.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 974287991 - 2² = 974287987 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (974287891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 487143995 + 487143996.

It is an arithmetic number, because the mean of its divisors is an integer number (487143996).

Almost surely, 2^974287991 is an apocalyptic number.

974287991 is a deficient number, since it is larger than the sum of its proper divisors (1).

974287991 is an equidigital number, since it uses as much as digits as its factorization.

974287991 is an evil number, because the sum of its binary digits is even.

The product of its digits is 2286144, while the sum is 56.

The square root of 974287991 is about 31213.5866410767. The cubic root of 974287991 is about 991.3548063387.

The spelling of 974287991 in words is "nine hundred seventy-four million, two hundred eighty-seven thousand, nine hundred ninety-one".