19628661 has 16 divisors (see below), whose sum is σ = 28304640. Its totient is φ = 12027840.

The previous prime is 19628639. The next prime is 19628663. The reversal of 19628661 is 16682691.

It is not a de Polignac number, because 19628661 - 2¹⁰ = 19627637 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19628663) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9556 + ... + 11426.

It is an arithmetic number, because the mean of its divisors is an integer number (1769040).

Almost surely, 2^19628661 is an apocalyptic number.

It is an amenable number.

19628661 is a deficient number, since it is larger than the sum of its proper divisors (8675979).

19628661 is a wasteful number, since it uses less digits than its factorization.

19628661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2156.

The product of its digits is 31104, while the sum is 39.

The square root of 19628661 is about 4430.4244717634. The cubic root of 19628661 is about 269.7513073547.

The spelling of 19628661 in words is "nineteen million, six hundred twenty-eight thousand, six hundred sixty-one".