19663974 has 48 divisors (see below), whose sum is σ = 48934080. Its totient is φ = 5644080.

The previous prime is 19663967. The next prime is 19663979. The reversal of 19663974 is 47936691.

19663974 is a `hidden beast` number, since 1 + 9 + 6 + 639 + 7 + 4 = 666.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19663979) 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, 1149 + ... + 6375.

It is an arithmetic number, because the mean of its divisors is an integer number (1019460).

Almost surely, 2^19663974 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19663974, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24467040).

19663974 is an abundant number, since it is smaller than the sum of its proper divisors (29270106).

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

19663974 is a wasteful number, since it uses less digits than its factorization.

19663974 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5265 (or 5262 counting only the distinct ones).

The product of its digits is 244944, while the sum is 45.

The square root of 19663974 is about 4434.4079649937. The cubic root of 19663974 is about 269.9129760695.

The spelling of 19663974 in words is "nineteen million, six hundred sixty-three thousand, nine hundred seventy-four".