256619501 has 2 divisors, whose sum is σ = 256619502. Its totient is φ = 256619500.

The previous prime is 256619479. The next prime is 256619509. The reversal of 256619501 is 105916652.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 249324100 + 7295401 = 15790^2 + 2701^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256619501 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 (256619509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128309750 + 128309751.

It is an arithmetic number, because the mean of its divisors is an integer number (128309751).

Almost surely, 2^256619501 is an apocalyptic number.

It is an amenable number.

256619501 is a deficient number, since it is larger than the sum of its proper divisors (1).

256619501 is an equidigital number, since it uses as much as digits as its factorization.

256619501 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16200, while the sum is 35.

The square root of 256619501 is about 16019.3477083182. The cubic root of 256619501 is about 635.4721938888.

The spelling of 256619501 in words is "two hundred fifty-six million, six hundred nineteen thousand, five hundred one".