256620105 has 36 divisors (see below), whose sum is σ = 517434372. Its totient is φ = 117311040.

The previous prime is 256620073. The next prime is 256620163. The reversal of 256620105 is 501026652.

256620105 is a `hidden beast` number, since 25 + 6 + 620 + 10 + 5 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 199148544 + 57471561 = 14112^2 + 7581^2 .

It is not a de Polignac number, because 256620105 - 2⁵ = 256620073 is a prime.

It is a super-2 number, since 2×256620105² = 131707756580422050, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 55986 + ... + 60395.

It is an arithmetic number, because the mean of its divisors is an integer number (14373177).

Almost surely, 2^256620105 is an apocalyptic number.

It is an amenable number.

256620105 is an abundant number, since it is smaller than the sum of its proper divisors (260814267).

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

256620105 is a wasteful number, since it uses less digits than its factorization.

256620105 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 116406 (or 116396 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

The square root of 256620105 is about 16019.3665605104. The cubic root of 256620105 is about 635.4726924543.

Adding to 256620105 its reverse (501026652), we get a palindrome (757646757).

The spelling of 256620105 in words is "two hundred fifty-six million, six hundred twenty thousand, one hundred five".