19722240 has 156 divisors (see below), whose sum is σ = 69000984. Its totient is φ = 5210112.

The previous prime is 19722217. The next prime is 19722259. The reversal of 19722240 is 4222791.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 184267 + ... + 184373.

It is an arithmetic number, because the mean of its divisors is an integer number (442314).

Almost surely, 2^19722240 is an apocalyptic number.

19722240 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 19722240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (34500492).

19722240 is an abundant number, since it is smaller than the sum of its proper divisors (49278744).

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

19722240 is a wasteful number, since it uses less digits than its factorization.

19722240 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 142 (or 117 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 19722240 is about 4440.9728663886. The cubic root of 19722240 is about 270.1793047671.

The spelling of 19722240 in words is "nineteen million, seven hundred twenty-two thousand, two hundred forty".