1921813480 has 32 divisors (see below), whose sum is σ = 4335008040. Its totient is φ = 766782720.

The previous prime is 1921813477. The next prime is 1921813489. The reversal of 1921813480 is 843181291.

It can be written as a sum of positive squares in 4 ways, for example, as 1111955716 + 809857764 = 33346^2 + 28458^2 .

It is a Smith number, since the sum of its digits (37) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (1921813489) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 44631 + ... + 76390.

Almost surely, 2^1921813480 is an apocalyptic number.

1921813480 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1921813480 is an abundant number, since it is smaller than the sum of its proper divisors (2413194560).

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

1921813480 is a wasteful number, since it uses less digits than its factorization.

1921813480 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 121429 (or 121425 counting only the distinct ones).

The product of its (nonzero) digits is 13824, while the sum is 37.

The square root of 1921813480 is about 43838.4931310372. The cubic root of 1921813480 is about 1243.2841920232.

The spelling of 1921813480 in words is "one billion, nine hundred twenty-one million, eight hundred thirteen thousand, four hundred eighty".