999879737257 has 2 divisors, whose sum is σ = 999879737258. Its totient is φ = 999879737256.

The previous prime is 999879737243. The next prime is 999879737281. The reversal of 999879737257 is 752737978999.

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., 582071340096 + 417808397161 = 762936^2 + 646381^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-999879737257 is a prime.

It is not a weakly prime, because it can be changed into another prime (999879737557) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499939868628 + 499939868629.

It is an arithmetic number, because the mean of its divisors is an integer number (499939868629).

Almost surely, 2^999879737257 is an apocalyptic number.

It is an amenable number.

999879737257 is a deficient number, since it is larger than the sum of its proper divisors (1).

999879737257 is an equidigital number, since it uses as much as digits as its factorization.

999879737257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3780710640, while the sum is 82.

The spelling of 999879737257 in words is "nine hundred ninety-nine billion, eight hundred seventy-nine million, seven hundred thirty-seven thousand, two hundred fifty-seven".