654957991 has 2 divisors, whose sum is σ = 654957992. Its totient is φ = 654957990.

The previous prime is 654957977. The next prime is 654958009. The reversal of 654957991 is 199759456.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 654957991 - 2²¹ = 652860839 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (654958991) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 327478995 + 327478996.

It is an arithmetic number, because the mean of its divisors is an integer number (327478996).

Almost surely, 2^654957991 is an apocalyptic number.

654957991 is a deficient number, since it is larger than the sum of its proper divisors (1).

654957991 is an equidigital number, since it uses as much as digits as its factorization.

654957991 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3061800, while the sum is 55.

The square root of 654957991 is about 25592.1470572518. The cubic root of 654957991 is about 868.4359935096.

The spelling of 654957991 in words is "six hundred fifty-four million, nine hundred fifty-seven thousand, nine hundred ninety-one".