221409792 has 60 divisors (see below), whose sum is σ = 639016950. Its totient is φ = 73801728.

The previous prime is 221409791. The next prime is 221409817. The reversal of 221409792 is 297904122.

It can be written as a sum of positive squares in only one way, i.e., 217149696 + 4260096 = 14736^2 + 2064^2 .

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (221409791) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 19417 + ... + 28632.

Almost surely, 2^221409792 is an apocalyptic number.

It is an amenable number.

221409792 is an abundant number, since it is smaller than the sum of its proper divisors (417607158).

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

221409792 is an equidigital number, since it uses as much as digits as its factorization.

221409792 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 48073 (or 48054 counting only the distinct ones).

The product of its (nonzero) digits is 18144, while the sum is 36.

The square root of 221409792 is about 14879.8451604847. The cubic root of 221409792 is about 604.9678210693.

The spelling of 221409792 in words is "two hundred twenty-one million, four hundred nine thousand, seven hundred ninety-two".