1256656280 has 32 divisors (see below), whose sum is σ = 3084521040. Its totient is φ = 456965760.

The previous prime is 1256656259. The next prime is 1256656307. The reversal of 1256656280 is 826566521.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1427579 + ... + 1428458.

Almost surely, 2^1256656280 is an apocalyptic number.

1256656280 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1256656280 is an abundant number, since it is smaller than the sum of its proper divisors (1827864760).

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

1256656280 is a wasteful number, since it uses less digits than its factorization.

1256656280 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2856059 (or 2856055 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 41.

The square root of 1256656280 is about 35449.3480899156. The cubic root of 1256656280 is about 1079.1260304875.

The spelling of 1256656280 in words is "one billion, two hundred fifty-six million, six hundred fifty-six thousand, two hundred eighty".