16921279 has 2 divisors, whose sum is σ = 16921280. Its totient is φ = 16921278.

The previous prime is 16921187. The next prime is 16921291. The reversal of 16921279 is 97212961.

It is a strong prime.

It is an emirp because it is prime and its reverse (97212961) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16921279 - 2¹³ = 16913087 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16921379) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8460639 + 8460640.

It is an arithmetic number, because the mean of its divisors is an integer number (8460640).

Almost surely, 2^16921279 is an apocalyptic number.

16921279 is a deficient number, since it is larger than the sum of its proper divisors (1).

16921279 is an equidigital number, since it uses as much as digits as its factorization.

16921279 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13608, while the sum is 37.

The square root of 16921279 is about 4113.5482250729. The cubic root of 16921279 is about 256.7306549480.

The spelling of 16921279 in words is "sixteen million, nine hundred twenty-one thousand, two hundred seventy-nine".