11921145839 has 4 divisors (see below), whose sum is σ = 11955304200. Its totient is φ = 11886987480.

The previous prime is 11921145827. The next prime is 11921145857. The reversal of 11921145839 is 93854112911.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 93854112911 = 13 ⋅7219547147.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11921145839 is a prime.

It is a super-2 number, since 2×11921145839² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 11921145839.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11921145239) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 17078657 + ... + 17079354.

It is an arithmetic number, because the mean of its divisors is an integer number (2988826050).

Almost surely, 2^11921145839 is an apocalyptic number.

11921145839 is a deficient number, since it is larger than the sum of its proper divisors (34158361).

11921145839 is an equidigital number, since it uses as much as digits as its factorization.

11921145839 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34158360.

The product of its digits is 77760, while the sum is 44.

The spelling of 11921145839 in words is "eleven billion, nine hundred twenty-one million, one hundred forty-five thousand, eight hundred thirty-nine".