1921650720 has 96 divisors (see below), whose sum is σ = 6603508800. Its totient is φ = 465853440.

The previous prime is 1921650719. The next prime is 1921650721. The reversal of 1921650720 is 270561291.

It is an interprime number because it is at equal distance from previous prime (1921650719) and next prime (1921650721).

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (33).

It is not an unprimeable number, because it can be changed into a prime (1921650721) 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, 176695 + ... + 187254.

It is an arithmetic number, because the mean of its divisors is an integer number (68786550).

Almost surely, 2^1921650720 is an apocalyptic number.

1921650720 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1921650720 is an abundant number, since it is smaller than the sum of its proper divisors (4681858080).

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

1921650720 is a wasteful number, since it uses less digits than its factorization.

1921650720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 363978 (or 363970 counting only the distinct ones).

The product of its (nonzero) digits is 7560, while the sum is 33.

The square root of 1921650720 is about 43836.6367323042. The cubic root of 1921650720 is about 1243.2490927711.

The spelling of 1921650720 in words is "one billion, nine hundred twenty-one million, six hundred fifty thousand, seven hundred twenty".