19979742 has 16 divisors (see below), whose sum is σ = 40008960. Its totient is φ = 6651672.

The previous prime is 19979737. The next prime is 19979759. The reversal of 19979742 is 24797991.

It is a happy number.

It is a junction number, because it is equal to n+sod(n) for n = 19979691 and 19979700.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5109 + ... + 8127.

It is an arithmetic number, because the mean of its divisors is an integer number (2500560).

Almost surely, 2^19979742 is an apocalyptic number.

19979742 is an abundant number, since it is smaller than the sum of its proper divisors (20029218).

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

19979742 is a wasteful number, since it uses less digits than its factorization.

19979742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4127.

The product of its digits is 285768, while the sum is 48.

The square root of 19979742 is about 4469.8704679219. The cubic root of 19979742 is about 271.3500829119.

The spelling of 19979742 in words is "nineteen million, nine hundred seventy-nine thousand, seven hundred forty-two".