221433749 has 4 divisors (see below), whose sum is σ = 222593280. Its totient is φ = 220274220.

The previous prime is 221433731. The next prime is 221433767. The reversal of 221433749 is 947334122.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (221433731) and next prime (221433767).

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-221433749 is a prime.

It is a Duffinian number.

It is a plaindrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221433769) 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, 579479 + ... + 579860.

It is an arithmetic number, because the mean of its divisors is an integer number (55648320).

Almost surely, 2^221433749 is an apocalyptic number.

It is an amenable number.

221433749 is a deficient number, since it is larger than the sum of its proper divisors (1159531).

221433749 is a wasteful number, since it uses less digits than its factorization.

221433749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1159530.

The product of its digits is 36288, while the sum is 35.

The square root of 221433749 is about 14880.6501538071. The cubic root of 221433749 is about 604.9896398745.

The spelling of 221433749 in words is "two hundred twenty-one million, four hundred thirty-three thousand, seven hundred forty-nine".