1921704564 has 48 divisors (see below), whose sum is σ = 4866971648. Its totient is φ = 586631808.

The previous prime is 1921704541. The next prime is 1921704569. The reversal of 1921704564 is 4654071291.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1921704569) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 28687 + ... + 68310.

Almost surely, 2^1921704564 is an apocalyptic number.

It is an amenable number.

1921704564 is an abundant number, since it is smaller than the sum of its proper divisors (2945267084).

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

1921704564 is a wasteful number, since it uses less digits than its factorization.

1921704564 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 97144 (or 97142 counting only the distinct ones).

The product of its (nonzero) digits is 60480, while the sum is 39.

The square root of 1921704564 is about 43837.2508718327. The cubic root of 1921704564 is about 1243.2607044683.

The spelling of 1921704564 in words is "one billion, nine hundred twenty-one million, seven hundred four thousand, five hundred sixty-four".