220864993 has 4 divisors (see below), whose sum is σ = 221442048. Its totient is φ = 220287940.

The previous prime is 220864979. The next prime is 220864997. The reversal of 220864993 is 399468022.

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 a de Polignac number, because none of the positive numbers 2^k-220864993 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (220864997) 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, 287953 + ... + 288718.

It is an arithmetic number, because the mean of its divisors is an integer number (55360512).

Almost surely, 2^220864993 is an apocalyptic number.

It is an amenable number.

220864993 is a deficient number, since it is larger than the sum of its proper divisors (577055).

220864993 is an equidigital number, since it uses as much as digits as its factorization.

220864993 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 577054.

The product of its (nonzero) digits is 186624, while the sum is 43.

The square root of 220864993 is about 14861.5272768313. The cubic root of 220864993 is about 604.4712206909.

The spelling of 220864993 in words is "two hundred twenty million, eight hundred sixty-four thousand, nine hundred ninety-three".