1161417891481 has 3 divisors (see below), whose sum is σ = 1161418969173. Its totient is φ = 1161416813790.

The previous prime is 1161417891433. The next prime is 1161417891503. The reversal of 1161417891481 is 1841987141611.

The square root of 1161417891481 is 1077691.

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 1161417891481 - 2³⁵ = 1127058153113 is a prime.

It is a super-2 number, since 2×1161417891481² (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 (1161417841481) 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, 538846 + ... + 1616536.

It is an arithmetic number, because the mean of its divisors is an integer number (387139656391).

Almost surely, 2^{1161417891481} is an apocalyptic number.

1161417891481 is the 1077691-st square number.

1161417891481 is the 538846-th centered octagonal number.

It is an amenable number.

1161417891481 is a deficient number, since it is larger than the sum of its proper divisors (1077692).

1161417891481 is an frugal number, since it uses more digits than its factorization.

1161417891481 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2155382 (or 1077691 counting only the distinct ones).

The product of its digits is 387072, while the sum is 52.

The spelling of 1161417891481 in words is "one trillion, one hundred sixty-one billion, four hundred seventeen million, eight hundred ninety-one thousand, four hundred eighty-one".