1281256964 has 48 divisors (see below), whose sum is σ = 2457087360. Its totient is φ = 581057280.

The previous prime is 1281256961. The next prime is 1281256967. The reversal of 1281256964 is 4696521821.

It is an interprime number because it is at equal distance from previous prime (1281256961) and next prime (1281256967).

It is not an unprimeable number, because it can be changed into a prime (1281256961) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 743624 + ... + 745344.

It is an arithmetic number, because the mean of its divisors is an integer number (51189320).

Almost surely, 2^1281256964 is an apocalyptic number.

It is an amenable number.

1281256964 is a deficient number, since it is larger than the sum of its proper divisors (1175830396).

1281256964 is a wasteful number, since it uses less digits than its factorization.

1281256964 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1980 (or 1978 counting only the distinct ones).

The product of its digits is 207360, while the sum is 44.

The square root of 1281256964 is about 35794.6499354303. The cubic root of 1281256964 is about 1086.1223392415.

The spelling of 1281256964 in words is "one billion, two hundred eighty-one million, two hundred fifty-six thousand, nine hundred sixty-four".