721822920 has 512 divisors, whose sum is σ = 2903040000. Its totient is φ = 142248960.

The previous prime is 721822919. The next prime is 721822957. The reversal of 721822920 is 29228127.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 10166485 + ... + 10166555.

It is an arithmetic number, because the mean of its divisors is an integer number (5670000).

Almost surely, 2^721822920 is an apocalyptic number.

721822920 is a gapful number since it is divisible by the number (70) 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 721822920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1451520000).

721822920 is an abundant number, since it is smaller than the sum of its proper divisors (2181217080).

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

721822920 is a wasteful number, since it uses less digits than its factorization.

721822920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 138 (or 120 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 721822920 is about 26866.7623654210. The cubic root of 721822920 is about 897.0367231665.

The spelling of 721822920 in words is "seven hundred twenty-one million, eight hundred twenty-two thousand, nine hundred twenty".