1918634981904 has 45 divisors (see below), whose sum is σ = 5369559696813. Its totient is φ = 639539453376.

The previous prime is 1918634981897. The next prime is 1918634981917. The reversal of 1918634981904 is 4091894368191.

The square root of 1918634981904 is 1385148.

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

It can be written as a sum of positive squares in only one way, i.e., 401008095504 + 1517626886400 = 633252^2 + 1231920^2 .

It is an unprimeable number.

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 8 ways as a sum of consecutive naturals, for example, 16564062 + ... + 16679490.

Almost surely, 2^{1918634981904} is an apocalyptic number.

1918634981904 is the 1385148-th square number.

It is an amenable number.

1918634981904 is an abundant number, since it is smaller than the sum of its proper divisors (3450924714909).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1918634981904 is an frugal number, since it uses more digits than its factorization.

1918634981904 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 230872 (or 115434 counting only the distinct ones).

The product of its (nonzero) digits is 13436928, while the sum is 63.

The spelling of 1918634981904 in words is "one trillion, nine hundred eighteen billion, six hundred thirty-four million, nine hundred eighty-one thousand, nine hundred four".