221117550 has 48 divisors (see below), whose sum is σ = 563206512. Its totient is φ = 57369600.

The previous prime is 221117549. The next prime is 221117557. The reversal of 221117550 is 55711122.

It is a self number, because there is not a number n which added to its sum of digits gives 221117550.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221117557) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14371 + ... + 25470.

It is an arithmetic number, because the mean of its divisors is an integer number (11733469).

Almost surely, 2^221117550 is an apocalyptic number.

221117550 is an abundant number, since it is smaller than the sum of its proper divisors (342088962).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

221117550 is a wasteful number, since it uses less digits than its factorization.

221117550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 39893 (or 39888 counting only the distinct ones).

The product of its (nonzero) digits is 700, while the sum is 24.

The square root of 221117550 is about 14870.0218560700. The cubic root of 221117550 is about 604.7015352724.

Adding to 221117550 its reverse (55711122), we get a palindrome (276828672).

The spelling of 221117550 in words is "two hundred twenty-one million, one hundred seventeen thousand, five hundred fifty".