256399799 has 2 divisors, whose sum is σ = 256399800. Its totient is φ = 256399798.

The previous prime is 256399783. The next prime is 256399807. The reversal of 256399799 is 997993652.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 256399799 - 2⁴ = 256399783 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256399739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128199899 + 128199900.

It is an arithmetic number, because the mean of its divisors is an integer number (128199900).

Almost surely, 2^256399799 is an apocalyptic number.

256399799 is a deficient number, since it is larger than the sum of its proper divisors (1).

256399799 is an equidigital number, since it uses as much as digits as its factorization.

256399799 is an evil number, because the sum of its binary digits is even.

The product of its digits is 8266860, while the sum is 59.

The square root of 256399799 is about 16012.4888446487. The cubic root of 256399799 is about 635.2907912369.

The spelling of 256399799 in words is "two hundred fifty-six million, three hundred ninety-nine thousand, seven hundred ninety-nine".