1247667664 has 60 divisors (see below), whose sum is σ = 2536048000. Its totient is φ = 594014400.

The previous prime is 1247667653. The next prime is 1247667697. The reversal of 1247667664 is 4667667421.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2500087 + ... + 2500585.

Almost surely, 2^1247667664 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 1247667664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1268024000).

1247667664 is an abundant number, since it is smaller than the sum of its proper divisors (1288380336).

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

1247667664 is an equidigital number, since it uses as much as digits as its factorization.

1247667664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 680 (or 603 counting only the distinct ones).

The product of its digits is 2032128, while the sum is 49.

The square root of 1247667664 is about 35322.3394468713. The cubic root of 1247667664 is about 1076.5469458056.

The spelling of 1247667664 in words is "one billion, two hundred forty-seven million, six hundred sixty-seven thousand, six hundred sixty-four".