1811921488 has 20 divisors (see below), whose sum is σ = 3780644308. Its totient is φ = 836271360.

The previous prime is 1811921483. The next prime is 1811921521. The reversal of 1811921488 is 8841291181.

It can be written as a sum of positive squares in 2 ways, for example, as 481714704 + 1330206784 = 21948^2 + 36472^2 .

It is a super-2 number, since 2×1811921488² = 6566118957352268288, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1811921483) 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, 4355373 + ... + 4355788.

Almost surely, 2^1811921488 is an apocalyptic number.

It is an amenable number.

1811921488 is an abundant number, since it is smaller than the sum of its proper divisors (1968722820).

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

1811921488 is a wasteful number, since it uses less digits than its factorization.

1811921488 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8711182 (or 8711176 counting only the distinct ones).

The product of its digits is 36864, while the sum is 43.

The square root of 1811921488 is about 42566.6710937090. The cubic root of 1811921488 is about 1219.1200068130.

The spelling of 1811921488 in words is "one billion, eight hundred eleven million, nine hundred twenty-one thousand, four hundred eighty-eight".