1373616561 has 4 divisors (see below), whose sum is σ = 1831488752. Its totient is φ = 915744372.

The previous prime is 1373616539. The next prime is 1373616637. The reversal of 1373616561 is 1656163731.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 1373616561 - 2²³ = 1365227953 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1373616161) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 228936091 + ... + 228936096.

It is an arithmetic number, because the mean of its divisors is an integer number (457872188).

Almost surely, 2^1373616561 is an apocalyptic number.

It is an amenable number.

1373616561 is a deficient number, since it is larger than the sum of its proper divisors (457872191).

1373616561 is an equidigital number, since it uses as much as digits as its factorization.

1373616561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 457872190.

The product of its digits is 68040, while the sum is 39.

The square root of 1373616561 is about 37062.3334532514. Note that the first 3 decimals coincide. The cubic root of 1373616561 is about 1111.6169818611.

The spelling of 1373616561 in words is "one billion, three hundred seventy-three million, six hundred sixteen thousand, five hundred sixty-one".