1091479578121 has 3 divisors (see below), whose sum is σ = 1091480622861. Its totient is φ = 1091478533382.

The previous prime is 1091479578103. The next prime is 1091479578131. The reversal of 1091479578121 is 1218759741901.

The square root of 1091479578121 is 1044739.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is not a de Polignac number, because 1091479578121 - 2²⁷ = 1091345360393 is a prime.

It is a super-2 number, since 2×1091479578121² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1091479578131) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 522370 + ... + 1567108.

It is an arithmetic number, because the mean of its divisors is an integer number (363826874287).

Almost surely, 2^{1091479578121} is an apocalyptic number.

1091479578121 is the 1044739-th square number.

1091479578121 is the 522370-th centered octagonal number.

It is an amenable number.

1091479578121 is a deficient number, since it is larger than the sum of its proper divisors (1044740).

1091479578121 is an frugal number, since it uses more digits than its factorization.

1091479578121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2089478 (or 1044739 counting only the distinct ones).

The product of its (nonzero) digits is 1270080, while the sum is 55.

The spelling of 1091479578121 in words is "one trillion, ninety-one billion, four hundred seventy-nine million, five hundred seventy-eight thousand, one hundred twenty-one".