221140391 has 4 divisors (see below), whose sum is σ = 228273984. Its totient is φ = 214006800.

The previous prime is 221140349. The next prime is 221140393. The reversal of 221140391 is 193041122.

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-221140391 is a prime.

It is a super-3 number, since 3×221140391³ (a number of 26 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221140393) 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, 3566750 + ... + 3566811.

It is an arithmetic number, because the mean of its divisors is an integer number (57068496).

Almost surely, 2^221140391 is an apocalyptic number.

221140391 is a deficient number, since it is larger than the sum of its proper divisors (7133593).

221140391 is an equidigital number, since it uses as much as digits as its factorization.

221140391 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7133592.

The product of its (nonzero) digits is 432, while the sum is 23.

The square root of 221140391 is about 14870.7898579732. The cubic root of 221140391 is about 604.7223560413.

The spelling of 221140391 in words is "two hundred twenty-one million, one hundred forty thousand, three hundred ninety-one".