1272927656 has 128 divisors (see below), whose sum is σ = 3283580160. Its totient is φ = 446515200.

The previous prime is 1272927631. The next prime is 1272927671. The reversal of 1272927656 is 6567292721.

It is an alternating number because its digits alternate between odd and even.

It is a self number, because there is not a number n which added to its sum of digits gives 1272927656.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 326390 + ... + 330266.

It is an arithmetic number, because the mean of its divisors is an integer number (25652970).

Almost surely, 2^1272927656 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1272927656, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1641790080).

1272927656 is an abundant number, since it is smaller than the sum of its proper divisors (2010652504).

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

1272927656 is a wasteful number, since it uses less digits than its factorization.

1272927656 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3955 (or 3951 counting only the distinct ones).

The product of its digits is 635040, while the sum is 47.

The square root of 1272927656 is about 35678.1117213341. Note that the first 3 decimals coincide. The cubic root of 1272927656 is about 1083.7636340531.

The spelling of 1272927656 in words is "one billion, two hundred seventy-two million, nine hundred twenty-seven thousand, six hundred fifty-six".