221501797 has 16 divisors (see below), whose sum is σ = 254090880. Its totient is φ = 191217600.

The previous prime is 221501779. The next prime is 221501801. The reversal of 221501797 is 797105122.

It is a cyclic number.

It is not a de Polignac number, because 221501797 - 2⁷ = 221501669 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 (221501717) 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, 13768 + ... + 25150.

It is an arithmetic number, because the mean of its divisors is an integer number (15880680).

Almost surely, 2^221501797 is an apocalyptic number.

It is an amenable number.

221501797 is a deficient number, since it is larger than the sum of its proper divisors (32589083).

221501797 is a wasteful number, since it uses less digits than its factorization.

221501797 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11484.

The product of its (nonzero) digits is 8820, while the sum is 34.

The square root of 221501797 is about 14882.9364374105. The cubic root of 221501797 is about 605.0516059160.

The spelling of 221501797 in words is "two hundred twenty-one million, five hundred one thousand, seven hundred ninety-seven".