511555997 has 2 divisors, whose sum is σ = 511555998. Its totient is φ = 511555996.

The previous prime is 511555991. The next prime is 511556033. The reversal of 511555997 is 799555115.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 419184676 + 92371321 = 20474^2 + 9611^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-511555997 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (511555991) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 255777998 + 255777999.

It is an arithmetic number, because the mean of its divisors is an integer number (255777999).

Almost surely, 2^511555997 is an apocalyptic number.

It is an amenable number.

511555997 is a deficient number, since it is larger than the sum of its proper divisors (1).

511555997 is an equidigital number, since it uses as much as digits as its factorization.

511555997 is an evil number, because the sum of its binary digits is even.

The product of its digits is 354375, while the sum is 47.

The square root of 511555997 is about 22617.6036971205. The cubic root of 511555997 is about 799.7686815587.

The spelling of 511555997 in words is "five hundred eleven million, five hundred fifty-five thousand, nine hundred ninety-seven".