19942864 has 10 divisors (see below), whose sum is σ = 38639330. Its totient is φ = 9971424.

The previous prime is 19942861. The next prime is 19942891. The reversal of 19942864 is 46824991.

It can be written as a sum of positive squares in only one way, i.e., 10942864 + 9000000 = 3308^2 + 3000^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 19942864.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19942861) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 623199 + ... + 623230.

It is an arithmetic number, because the mean of its divisors is an integer number (3863933).

Almost surely, 2^19942864 is an apocalyptic number.

It is an amenable number.

19942864 is a deficient number, since it is larger than the sum of its proper divisors (18696466).

19942864 is a wasteful number, since it uses less digits than its factorization.

19942864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1246437 (or 1246431 counting only the distinct ones).

The product of its digits is 124416, while the sum is 43.

The square root of 19942864 is about 4465.7433871641. The cubic root of 19942864 is about 271.1830301799.

The spelling of 19942864 in words is "nineteen million, nine hundred forty-two thousand, eight hundred sixty-four".