221931930 has 32 divisors (see below), whose sum is σ = 581059008. Its totient is φ = 53801600.

The previous prime is 221931929. The next prime is 221931953. The reversal of 221931930 is 39139122.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 335931 + ... + 336590.

It is an arithmetic number, because the mean of its divisors is an integer number (18158094).

Almost surely, 2^221931930 is an apocalyptic number.

221931930 is an abundant number, since it is smaller than the sum of its proper divisors (359127078).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221931930 is a wasteful number, since it uses less digits than its factorization.

221931930 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 672542.

The product of its (nonzero) digits is 2916, while the sum is 30.

The square root of 221931930 is about 14897.3799709882. The cubic root of 221931930 is about 605.4430013605.

The spelling of 221931930 in words is "two hundred twenty-one million, nine hundred thirty-one thousand, nine hundred thirty".