11961165625 has 12 divisors (see below), whose sum is σ = 14950504044. Its totient is φ = 9568930000.

The previous prime is 11961165611. The next prime is 11961165631. The reversal of 11961165625 is 52656116911.

It can be written as a sum of positive squares in 6 ways, for example, as 7583623056 + 4377542569 = 87084^2 + 66163^2 .

It is not a de Polignac number, because 11961165625 - 2⁷ = 11961165497 is a prime.

It is a super-3 number, since 3×11961165625³ (a number of 31 digits) contains 333 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1910662 + ... + 1916911.

It is an arithmetic number, because the mean of its divisors is an integer number (1245875337).

Almost surely, 2^11961165625 is an apocalyptic number.

It is an amenable number.

11961165625 is a deficient number, since it is larger than the sum of its proper divisors (2989338419).

11961165625 is an frugal number, since it uses more digits than its factorization.

11961165625 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3827598 (or 3827578 counting only the distinct ones).

The product of its digits is 97200, while the sum is 43.

The spelling of 11961165625 in words is "eleven billion, nine hundred sixty-one million, one hundred sixty-five thousand, six hundred twenty-five".