223013721 has 32 divisors (see below), whose sum is σ = 356098048. Its totient is φ = 121461120.

The previous prime is 223013717. The next prime is 223013723. The reversal of 223013721 is 127310322.

It is not a de Polignac number, because 223013721 - 2² = 223013717 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (223013723) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 41061 + ... + 46173.

It is an arithmetic number, because the mean of its divisors is an integer number (11128064).

Almost surely, 2^223013721 is an apocalyptic number.

223013721 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

223013721 is a deficient number, since it is larger than the sum of its proper divisors (133084327).

223013721 is a wasteful number, since it uses less digits than its factorization.

223013721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5221.

The product of its (nonzero) digits is 504, while the sum is 21.

The square root of 223013721 is about 14933.6439290617. The cubic root of 223013721 is about 606.4251365479.

It can be divided in two parts, 2230 and 13721, that added together give a palindrome (15951).

The spelling of 223013721 in words is "two hundred twenty-three million, thirteen thousand, seven hundred twenty-one".