1247664408 has 32 divisors (see below), whose sum is σ = 3302642160. Its totient is φ = 391424000.

The previous prime is 1247664401. The next prime is 1247664427. The reversal of 1247664408 is 8044667421.

It is a self number, because there is not a number n which added to its sum of digits gives 1247664408.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1247664401) 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, 1528593 + ... + 1529408.

Almost surely, 2^1247664408 is an apocalyptic number.

It is an amenable number.

1247664408 is an abundant number, since it is smaller than the sum of its proper divisors (2054977752).

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

1247664408 is a wasteful number, since it uses less digits than its factorization.

1247664408 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3058027 (or 3058023 counting only the distinct ones).

The product of its (nonzero) digits is 258048, while the sum is 42.

The square root of 1247664408 is about 35322.2933570288. The cubic root of 1247664408 is about 1076.5460093276.

The spelling of 1247664408 in words is "one billion, two hundred forty-seven million, six hundred sixty-four thousand, four hundred eight".