19901742 has 48 divisors (see below), whose sum is σ = 46730880. Its totient is φ = 5633712.

The previous prime is 19901737. The next prime is 19901753. The reversal of 19901742 is 24710991.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 40623 + ... + 41109.

It is an arithmetic number, because the mean of its divisors is an integer number (973560).

Almost surely, 2^19901742 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19901742, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23365440).

19901742 is an abundant number, since it is smaller than the sum of its proper divisors (26829138).

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

19901742 is a wasteful number, since it uses less digits than its factorization.

19901742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 645 (or 638 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 33.

The square root of 19901742 is about 4461.1368506245. The cubic root of 19901742 is about 270.9965096249.

Subtracting 19901742 from its reverse (24710991), we obtain a square (4809249 = 2193²).

The spelling of 19901742 in words is "nineteen million, nine hundred one thousand, seven hundred forty-two".