220997279 has 4 divisors (see below), whose sum is σ = 222320784. Its totient is φ = 219673776.

The previous prime is 220997269. The next prime is 220997291. The reversal of 220997279 is 972799022.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-220997279 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 (220997209) 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, 661502 + ... + 661835.

It is an arithmetic number, because the mean of its divisors is an integer number (55580196).

Almost surely, 2^220997279 is an apocalyptic number.

220997279 is a deficient number, since it is larger than the sum of its proper divisors (1323505).

220997279 is a wasteful number, since it uses less digits than its factorization.

220997279 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1323504.

The product of its (nonzero) digits is 285768, while the sum is 47.

The square root of 220997279 is about 14865.9772299032. The cubic root of 220997279 is about 604.5918782920.

The spelling of 220997279 in words is "two hundred twenty million, nine hundred ninety-seven thousand, two hundred seventy-nine".