726173521920 has 1152 divisors, whose sum is σ = 3240013271040. Its totient is φ = 145981440000.

The previous prime is 726173521907. The next prime is 726173521979. The reversal of 726173521920 is 29125371627.

It is a happy number.

726173521920 is a `hidden beast` number, since 7 + 2 + 617 + 3 + 5 + 2 + 1 + 9 + 20 = 666.

It is a tau number, because it is divible by the number of its divisors (1152).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 219984270 + ... + 219987570.

It is an arithmetic number, because the mean of its divisors is an integer number (2812511520).

Almost surely, 2^726173521920 is an apocalyptic number.

726173521920 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 726173521920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1620006635520).

726173521920 is an abundant number, since it is smaller than the sum of its proper divisors (2513839749120).

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

726173521920 is a wasteful number, since it uses less digits than its factorization.

726173521920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3383 (or 3360 counting only the distinct ones).

The product of its (nonzero) digits is 317520, while the sum is 45.

The spelling of 726173521920 in words is "seven hundred twenty-six billion, one hundred seventy-three million, five hundred twenty-one thousand, nine hundred twenty".