11637878641 has 9 divisors (see below), whose sum is σ = 11713339659. Its totient is φ = 11562902736.

The previous prime is 11637878599. The next prime is 11637878677. The reversal of 11637878641 is 14687873611.

It is a happy number.

The square root of 11637878641 is 107879.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 2363418225 + 9274460416 = 48615^2 + 96304^2 .

It is a de Polignac number, because none of the positive numbers 2^k-11637878641 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11637878041) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 25135576 + ... + 25136038.

Almost surely, 2^11637878641 is an apocalyptic number.

11637878641 is the 107879-th square number.

11637878641 is the 53940-th centered octagonal number.

It is an amenable number.

11637878641 is a deficient number, since it is larger than the sum of its proper divisors (75461018).

11637878641 is an frugal number, since it uses more digits than its factorization.

11637878641 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1392 (or 696 counting only the distinct ones).

The product of its digits is 1354752, while the sum is 52.

The spelling of 11637878641 in words is "eleven billion, six hundred thirty-seven million, eight hundred seventy-eight thousand, six hundred forty-one".