1373921881 has 4 divisors (see below), whose sum is σ = 1374178212. Its totient is φ = 1373665552.

The previous prime is 1373921821. The next prime is 1373921921. The reversal of 1373921881 is 1881293731.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1348064656 + 25857225 = 36716^2 + 5085^2 .

It is a cyclic number.

It is not a de Polignac number, because 1373921881 - 2¹⁷ = 1373790809 is a prime.

It is a super-2 number, since 2×1373921881² = 3775322670181156322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1373921821) 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, 119950 + ... + 130903.

It is an arithmetic number, because the mean of its divisors is an integer number (343544553).

Almost surely, 2^1373921881 is an apocalyptic number.

It is an amenable number.

1373921881 is a deficient number, since it is larger than the sum of its proper divisors (256331).

1373921881 is an equidigital number, since it uses as much as digits as its factorization.

1373921881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 256330.

The product of its digits is 72576, while the sum is 43.

The square root of 1373921881 is about 37066.4522310944. The cubic root of 1373921881 is about 1111.6993371469.

The spelling of 1373921881 in words is "one billion, three hundred seventy-three million, nine hundred twenty-one thousand, eight hundred eighty-one".