221071990 has 32 divisors (see below), whose sum is σ = 407586816. Its totient is φ = 86308320.

The previous prime is 221071979. The next prime is 221071999. The reversal of 221071990 is 99170122.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221071999) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 71619 + ... + 74641.

It is an arithmetic number, because the mean of its divisors is an integer number (12737088).

Almost surely, 2^221071990 is an apocalyptic number.

221071990 is a deficient number, since it is larger than the sum of its proper divisors (186514826).

221071990 is a wasteful number, since it uses less digits than its factorization.

221071990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3204.

The product of its (nonzero) digits is 2268, while the sum is 31.

The square root of 221071990 is about 14868.4898358912. The cubic root of 221071990 is about 604.6600006613.

The spelling of 221071990 in words is "two hundred twenty-one million, seventy-one thousand, nine hundred ninety".