221284990 has 32 divisors (see below), whose sum is σ = 405984960. Its totient is φ = 86822400.

The previous prime is 221284981. The next prime is 221285011. The reversal of 221284990 is 99482122.

221284990 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

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, 161910 + ... + 163270.

It is an arithmetic number, because the mean of its divisors is an integer number (12687030).

Almost surely, 2^221284990 is an apocalyptic number.

221284990 is a deficient number, since it is larger than the sum of its proper divisors (184699970).

221284990 is a wasteful number, since it uses less digits than its factorization.

221284990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1668.

The product of its (nonzero) digits is 20736, while the sum is 37.

The square root of 221284990 is about 14875.6509101283. The cubic root of 221284990 is about 604.8541323541.

The spelling of 221284990 in words is "two hundred twenty-one million, two hundred eighty-four thousand, nine hundred ninety".