16779621 has 8 divisors (see below), whose sum is σ = 22549504. Its totient is φ = 11098080.

The previous prime is 16779599. The next prime is 16779647. The reversal of 16779621 is 12697761.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a de Polignac number, because none of the positive numbers 2^k-16779621 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 16779621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16779671) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 21640 + ... + 22401.

It is an arithmetic number, because the mean of its divisors is an integer number (2818688).

Almost surely, 2^16779621 is an apocalyptic number.

It is an amenable number.

16779621 is a deficient number, since it is larger than the sum of its proper divisors (5769883).

16779621 is a wasteful number, since it uses less digits than its factorization.

16779621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44171.

The product of its digits is 31752, while the sum is 39.

The square root of 16779621 is about 4096.2935685812. The cubic root of 16779621 is about 256.0122318781.

The spelling of 16779621 in words is "sixteen million, seven hundred seventy-nine thousand, six hundred twenty-one".