27400511961 has 27 divisors (see below), whose sum is σ = 41391393589. Its totient is φ = 17465506872.

The previous prime is 27400511959. The next prime is 27400512031. The reversal of 27400511961 is 16911500472.

The square root of 27400511961 is 165531.

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

It is not a de Polignac number, because 27400511961 - 2¹ = 27400511959 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27400511261) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 11420440 + ... + 11422838.

Almost surely, 2^27400511961 is an apocalyptic number.

27400511961 is the 165531-st square number.

27400511961 is the 82766-th centered octagonal number.

It is an amenable number.

27400511961 is a deficient number, since it is larger than the sum of its proper divisors (13990881628).

27400511961 is an frugal number, since it uses more digits than its factorization.

27400511961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4850 (or 2425 counting only the distinct ones).

The product of its (nonzero) digits is 15120, while the sum is 36.

Multiplying 27400511961 by its sum of digits (36), we get a square (986418430596 = 993186²).

The spelling of 27400511961 in words is "twenty-seven billion, four hundred million, five hundred eleven thousand, nine hundred sixty-one".