11391820525 has 12 divisors (see below), whose sum is σ = 14146867732. Its totient is φ = 9099901440.

The previous prime is 11391820501. The next prime is 11391820529. The reversal of 11391820525 is 52502819311.

It can be written as a sum of positive squares in 6 ways, for example, as 1395620164 + 9996200361 = 37358^2 + 99981^2 .

It is not a de Polignac number, because 11391820525 - 2¹⁷ = 11391689453 is a prime.

It is a super-2 number, since 2×11391820525² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11391820529) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 321714 + ... + 355363.

Almost surely, 2^11391820525 is an apocalyptic number.

It is an amenable number.

11391820525 is a deficient number, since it is larger than the sum of its proper divisors (2755047207).

11391820525 is an equidigital number, since it uses as much as digits as its factorization.

11391820525 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 677760 (or 677755 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 37.

The spelling of 11391820525 in words is "eleven billion, three hundred ninety-one million, eight hundred twenty thousand, five hundred twenty-five".