1253640647 has 8 divisors (see below), whose sum is σ = 1461972000. Its totient is φ = 1074548832.

The previous prime is 1253640637. The next prime is 1253640667. The reversal of 1253640647 is 7460463521.

It is a happy number.

It is not a de Polignac number, because 1253640647 - 2⁴ = 1253640631 is a prime.

It is a super-2 number, since 2×1253640647² = 3143229743621157218, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1253640647.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1253640617) 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, 1827122 + ... + 1827807.

It is an arithmetic number, because the mean of its divisors is an integer number (182746500).

Almost surely, 2^1253640647 is an apocalyptic number.

1253640647 is a deficient number, since it is larger than the sum of its proper divisors (208331353).

1253640647 is an frugal number, since it uses more digits than its factorization.

1253640647 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3654950 (or 3654936 counting only the distinct ones).

The product of its (nonzero) digits is 120960, while the sum is 38.

The square root of 1253640647 is about 35406.7881486022. The cubic root of 1253640647 is about 1078.2621361727.

The spelling of 1253640647 in words is "one billion, two hundred fifty-three million, six hundred forty thousand, six hundred forty-seven".