27979611261 has 32 divisors (see below), whose sum is σ = 45139107840. Its totient is φ = 15059265984.

The previous prime is 27979611259. The next prime is 27979611269. The reversal of 27979611261 is 16211697972.

It is not a de Polignac number, because 27979611261 - 2¹ = 27979611259 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27979611269) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 133645 + ... + 271698.

It is an arithmetic number, because the mean of its divisors is an integer number (1410597120).

Almost surely, 2^27979611261 is an apocalyptic number.

27979611261 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

27979611261 is a deficient number, since it is larger than the sum of its proper divisors (17159496579).

27979611261 is a wasteful number, since it uses less digits than its factorization.

27979611261 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 405545.

The product of its digits is 571536, while the sum is 51.

The spelling of 27979611261 in words is "twenty-seven billion, nine hundred seventy-nine million, six hundred eleven thousand, two hundred sixty-one".