221780697 has 8 divisors (see below), whose sum is σ = 308564544. Its totient is φ = 141425328.

The previous prime is 221780687. The next prime is 221780707. The reversal of 221780697 is 796087122.

221780697 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (221780687) and next prime (221780707).

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

It is not a de Polignac number, because 221780697 - 2⁴ = 221780681 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221780677) 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, 1607038 + ... + 1607175.

It is an arithmetic number, because the mean of its divisors is an integer number (38570568).

Almost surely, 2^221780697 is an apocalyptic number.

It is an amenable number.

221780697 is a deficient number, since it is larger than the sum of its proper divisors (86783847).

221780697 is a wasteful number, since it uses less digits than its factorization.

221780697 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3214239.

The product of its (nonzero) digits is 84672, while the sum is 42.

The square root of 221780697 is about 14892.3032805540. The cubic root of 221780697 is about 605.3054460187.

The spelling of 221780697 in words is "two hundred twenty-one million, seven hundred eighty thousand, six hundred ninety-seven".