19926661 has 4 divisors (see below), whose sum is σ = 19950112. Its totient is φ = 19903212.

The previous prime is 19926619. The next prime is 19926691. The reversal of 19926661 is 16662991.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 19926661 - 2²¹ = 17829509 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19926691) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10401 + ... + 12166.

It is an arithmetic number, because the mean of its divisors is an integer number (4987528).

Almost surely, 2^19926661 is an apocalyptic number.

It is an amenable number.

19926661 is a deficient number, since it is larger than the sum of its proper divisors (23451).

19926661 is an equidigital number, since it uses as much as digits as its factorization.

19926661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23450.

The product of its digits is 34992, while the sum is 40.

The square root of 19926661 is about 4463.9288748814. The cubic root of 19926661 is about 271.1095674922.

The spelling of 19926661 in words is "nineteen million, nine hundred twenty-six thousand, six hundred sixty-one".