1918056033721 has 27 divisors (see below), whose sum is σ = 2089478996877. Its totient is φ = 1760312866560.

The previous prime is 1918056033683. The next prime is 1918056033737. The reversal of 1918056033721 is 1273306508191.

It is a happy number.

The square root of 1918056033721 is 1384939.

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

It can be written as a sum of positive squares in 4 ways, for example, as 135126084025 + 1782929949696 = 367595^2 + 1335264^2 .

It is not a de Polignac number, because 1918056033721 - 2²⁷ = 1917921815993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1918056033791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 965301490 + ... + 965303476.

Almost surely, 2^{1918056033721} is an apocalyptic number.

1918056033721 is the 1384939-th square number.

1918056033721 is the 692470-th centered octagonal number.

It is an amenable number.

1918056033721 is a deficient number, since it is larger than the sum of its proper divisors (171422963156).

1918056033721 is an frugal number, since it uses more digits than its factorization.

1918056033721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4090 (or 2045 counting only the distinct ones).

The product of its (nonzero) digits is 272160, while the sum is 46.

The spelling of 1918056033721 in words is "one trillion, nine hundred eighteen billion, fifty-six million, thirty-three thousand, seven hundred twenty-one".