1921768464 has 120 divisors (see below), whose sum is σ = 6236614720. Its totient is φ = 499150080.

The previous prime is 1921768447. The next prime is 1921768487. The reversal of 1921768464 is 4648671291.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 17022 + ... + 64290.

Almost surely, 2^1921768464 is an apocalyptic number.

1921768464 is a gapful number since it is divisible by the number (14) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1921768464, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3118307360).

1921768464 is an abundant number, since it is smaller than the sum of its proper divisors (4314846256).

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

1921768464 is a wasteful number, since it uses less digits than its factorization.

1921768464 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47309 (or 47292 counting only the distinct ones).

The product of its digits is 580608, while the sum is 48.

The square root of 1921768464 is about 43837.9796979742. The cubic root of 1921768464 is about 1243.2744845050.

The spelling of 1921768464 in words is "one billion, nine hundred twenty-one million, seven hundred sixty-eight thousand, four hundred sixty-four".