19906720 has 48 divisors (see below), whose sum is σ = 47628000. Its totient is φ = 7861504.

The previous prime is 19906697. The next prime is 19906723. The reversal of 19906720 is 2760991.

It is a super-3 number, since 3×19906720³ (a number of 23 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (19906723) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12531 + ... + 14029.

It is an arithmetic number, because the mean of its divisors is an integer number (992250).

Almost surely, 2^19906720 is an apocalyptic number.

19906720 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 19906720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23814000).

19906720 is an abundant number, since it is smaller than the sum of its proper divisors (27721280).

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

19906720 is a wasteful number, since it uses less digits than its factorization.

19906720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1597 (or 1589 counting only the distinct ones).

The product of its (nonzero) digits is 6804, while the sum is 34.

The square root of 19906720 is about 4461.6947452734. The cubic root of 19906720 is about 271.0191024238.

The spelling of 19906720 in words is "nineteen million, nine hundred six thousand, seven hundred twenty".