1921820910 has 32 divisors (see below), whose sum is σ = 4613555232. Its totient is φ = 512353920.

The previous prime is 1921820903. The next prime is 1921820933. The reversal of 1921820910 is 190281291.

It is a super-2 number, since 2×1921820910² = 7386791220226456200, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 184440 + ... + 194580.

It is an arithmetic number, because the mean of its divisors is an integer number (144173601).

Almost surely, 2^1921820910 is an apocalyptic number.

1921820910 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1921820910 is an abundant number, since it is smaller than the sum of its proper divisors (2691734322).

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

1921820910 is a wasteful number, since it uses less digits than its factorization.

1921820910 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16468.

The product of its (nonzero) digits is 2592, while the sum is 33.

The square root of 1921820910 is about 43838.5778738316. The cubic root of 1921820910 is about 1243.2857942581.

The spelling of 1921820910 in words is "one billion, nine hundred twenty-one million, eight hundred twenty thousand, nine hundred ten".