23191297920 has 640 divisors, whose sum is σ = 95402672640. Its totient is φ = 5280712704.

The previous prime is 23191297891. The next prime is 23191297967. The reversal of 23191297920 is 2979219132.

It is a tau number, because it is divible by the number of its divisors (640).

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 pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 88179709 + ... + 88179971.

It is an arithmetic number, because the mean of its divisors is an integer number (149066676).

Almost surely, 2^23191297920 is an apocalyptic number.

23191297920 is a gapful number since it is divisible by the number (20) 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 23191297920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47701336320).

23191297920 is an abundant number, since it is smaller than the sum of its proper divisors (72211374720).

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

23191297920 is an frugal number, since it uses more digits than its factorization.

23191297920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 316 (or 280 counting only the distinct ones).

The product of its (nonzero) digits is 122472, while the sum is 45.

The spelling of 23191297920 in words is "twenty-three billion, one hundred ninety-one million, two hundred ninety-seven thousand, nine hundred twenty".