11721937920 has 1056 divisors, whose sum is σ = 50808570624. Its totient is φ = 2249195520.

The previous prime is 11721937889. The next prime is 11721937933. The reversal of 11721937920 is 2973912711.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (1056).

It is a Harshad number since it is a multiple of its sum of digits (42).

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, 221168614 + ... + 221168666.

Almost surely, 2^11721937920 is an apocalyptic number.

11721937920 is a gapful number since it is divisible by the number (10) 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 11721937920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25404285312).

11721937920 is an abundant number, since it is smaller than the sum of its proper divisors (39086632704).

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

11721937920 is a wasteful number, since it uses less digits than its factorization.

11721937920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 127 (or 98 counting only the distinct ones).

The product of its (nonzero) digits is 47628, while the sum is 42.

The spelling of 11721937920 in words is "eleven billion, seven hundred twenty-one million, nine hundred thirty-seven thousand, nine hundred twenty".