1297636540 has 48 divisors (see below), whose sum is σ = 2993195520. Its totient is φ = 470352960.

The previous prime is 1297636519. The next prime is 1297636567. The reversal of 1297636540 is 456367921.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 65496 + ... + 82975.

It is an arithmetic number, because the mean of its divisors is an integer number (62358240).

Almost surely, 2^1297636540 is an apocalyptic number.

1297636540 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1297636540 is an abundant number, since it is smaller than the sum of its proper divisors (1695558980).

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

1297636540 is a wasteful number, since it uses less digits than its factorization.

1297636540 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 148522 (or 148520 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 43.

The square root of 1297636540 is about 36022.7225511898. The cubic root of 1297636540 is about 1090.7310809589.

The spelling of 1297636540 in words is "one billion, two hundred ninety-seven million, six hundred thirty-six thousand, five hundred forty".