11976894721 has 9 divisors (see below), whose sum is σ = 13166009283. Its totient is φ = 10886991720.

The previous prime is 11976894697. The next prime is 11976894781. The reversal of 11976894721 is 12749867911.

It is a happy number.

The square root of 11976894721 is 109439.

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., 4728075121 + 7248819600 = 68761^2 + 85140^2 .

It is not a de Polignac number, because 11976894721 - 2¹¹ = 11976892673 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (11976894781) 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, 1198855 + ... + 1208803.

Almost surely, 2^11976894721 is an apocalyptic number.

11976894721 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

11976894721 is the 109439-th square number.

11976894721 is the 54720-th centered octagonal number.

It is an amenable number.

11976894721 is a deficient number, since it is larger than the sum of its proper divisors (1189114562).

11976894721 is an frugal number, since it uses more digits than its factorization.

11976894721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19920 (or 9960 counting only the distinct ones).

The product of its digits is 1524096, while the sum is 55.

The spelling of 11976894721 in words is "eleven billion, nine hundred seventy-six million, eight hundred ninety-four thousand, seven hundred twenty-one".