19974864 has 160 divisors (see below), whose sum is σ = 67495680. Its totient is φ = 4939776.

The previous prime is 19974839. The next prime is 19974869. The reversal of 19974864 is 46847991.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19974869) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 74122 + ... + 74390.

It is an arithmetic number, because the mean of its divisors is an integer number (421848).

Almost surely, 2^19974864 is an apocalyptic number.

19974864 is a gapful number since it is divisible by the number (14) 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 19974864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (33747840).

19974864 is an abundant number, since it is smaller than the sum of its proper divisors (47520816).

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

19974864 is a wasteful number, since it uses less digits than its factorization.

19974864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 317 (or 311 counting only the distinct ones).

The product of its digits is 435456, while the sum is 48.

The square root of 19974864 is about 4469.3247812170. The cubic root of 19974864 is about 271.3279979848.

The spelling of 19974864 in words is "nineteen million, nine hundred seventy-four thousand, eight hundred sixty-four".