256414021 has 2 divisors, whose sum is σ = 256414022. Its totient is φ = 256414020.

The previous prime is 256414007. The next prime is 256414061. The reversal of 256414021 is 120414652.

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., 207763396 + 48650625 = 14414^2 + 6975^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-256414021 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (256414061) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 128207010 + 128207011.

It is an arithmetic number, because the mean of its divisors is an integer number (128207011).

Almost surely, 2^256414021 is an apocalyptic number.

It is an amenable number.

256414021 is a deficient number, since it is larger than the sum of its proper divisors (1).

256414021 is an equidigital number, since it uses as much as digits as its factorization.

256414021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1920, while the sum is 25.

The square root of 256414021 is about 16012.9329293543. The cubic root of 256414021 is about 635.3025371361.

Adding to 256414021 its reverse (120414652), we get a palindrome (376828673).

The spelling of 256414021 in words is "two hundred fifty-six million, four hundred fourteen thousand, twenty-one".