19771872 has 24 divisors (see below), whose sum is σ = 51901416. Its totient is φ = 6590592.

The previous prime is 19771841. The next prime is 19771879. The reversal of 19771872 is 27817791.

It is a tau number, because it is divible by the number of its divisors (24).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19771879) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 102883 + ... + 103074.

It is an arithmetic number, because the mean of its divisors is an integer number (2162559).

Almost surely, 2^19771872 is an apocalyptic number.

19771872 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

19771872 is an abundant number, since it is smaller than the sum of its proper divisors (32129544).

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

19771872 is a wasteful number, since it uses less digits than its factorization.

19771872 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 205970 (or 205962 counting only the distinct ones).

The product of its digits is 49392, while the sum is 42.

The square root of 19771872 is about 4446.5573199949. The cubic root of 19771872 is about 270.4057548114.

The spelling of 19771872 in words is "nineteen million, seven hundred seventy-one thousand, eight hundred seventy-two".