221680607 has 4 divisors (see below), whose sum is σ = 222481176. Its totient is φ = 220880040.

The previous prime is 221680583. The next prime is 221680621. The reversal of 221680607 is 706086122.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221680607 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221680307) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 399869 + ... + 400422.

It is an arithmetic number, because the mean of its divisors is an integer number (55620294).

Almost surely, 2^221680607 is an apocalyptic number.

221680607 is a deficient number, since it is larger than the sum of its proper divisors (800569).

221680607 is an equidigital number, since it uses as much as digits as its factorization.

221680607 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 800568.

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 221680607 is about 14888.9424406168. The cubic root of 221680607 is about 605.2143738631.

The spelling of 221680607 in words is "two hundred twenty-one million, six hundred eighty thousand, six hundred seven".