19617972 has 72 divisors (see below), whose sum is σ = 51391200. Its totient is φ = 5818560.

The previous prime is 19617953. The next prime is 19617973. The reversal of 19617972 is 27971691.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19617973) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 85554 + ... + 85782.

Almost surely, 2^19617972 is an apocalyptic number.

19617972 is a gapful number since it is divisible by the number (12) 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 19617972, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (25695600).

19617972 is an abundant number, since it is smaller than the sum of its proper divisors (31773228).

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

19617972 is a wasteful number, since it uses less digits than its factorization.

19617972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 317 (or 304 counting only the distinct ones).

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

The square root of 19617972 is about 4429.2179896682. The cubic root of 19617972 is about 269.7023331315.

It can be divided in two parts, 196179 and 72, that added together give a triangular number (196251 = T₆₂₆).

The spelling of 19617972 in words is "nineteen million, six hundred seventeen thousand, nine hundred seventy-two".