256642122 has 16 divisors (see below), whose sum is σ = 559946592. Its totient is φ = 77770320.

The previous prime is 256642121. The next prime is 256642129. The reversal of 256642122 is 221246652.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 256642122.

It is not an unprimeable number, because it can be changed into a prime (256642121) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1944193 + ... + 1944324.

It is an arithmetic number, because the mean of its divisors is an integer number (34996662).

Almost surely, 2^256642122 is an apocalyptic number.

256642122 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

256642122 is an abundant number, since it is smaller than the sum of its proper divisors (303304470).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

256642122 is a wasteful number, since it uses less digits than its factorization.

256642122 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3888533.

The product of its digits is 11520, while the sum is 30.

The square root of 256642122 is about 16020.0537452282. The cubic root of 256642122 is about 635.4908656240.

Adding to 256642122 its reverse (221246652), we get a palindrome (477888774).

The spelling of 256642122 in words is "two hundred fifty-six million, six hundred forty-two thousand, one hundred twenty-two".