221490787 has 8 divisors (see below), whose sum is σ = 253222400. Its totient is φ = 189781704.

The previous prime is 221490767. The next prime is 221490791. The reversal of 221490787 is 787094122.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 221490787 - 2¹¹ = 221488739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (221490707) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35014 + ... + 40852.

It is an arithmetic number, because the mean of its divisors is an integer number (31652800).

Almost surely, 2^221490787 is an apocalyptic number.

221490787 is a deficient number, since it is larger than the sum of its proper divisors (31731613).

221490787 is an equidigital number, since it uses as much as digits as its factorization.

221490787 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11265.

The product of its (nonzero) digits is 56448, while the sum is 40.

The square root of 221490787 is about 14882.5665461304. The cubic root of 221490787 is about 605.0415808227.

The spelling of 221490787 in words is "two hundred twenty-one million, four hundred ninety thousand, seven hundred eighty-seven".