221156992 has 96 divisors (see below), whose sum is σ = 526922820. Its totient is φ = 92123136.

The previous prime is 221156989. The next prime is 221157011. The reversal of 221156992 is 299651122.

It can be written as a sum of positive squares in 2 ways, for example, as 213627456 + 7529536 = 14616^2 + 2744^2 .

It is a super-2 number, since 2×221156992² = 97820830220976128, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (37).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 231588 + ... + 232540.

Almost surely, 2^221156992 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221156992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (263461410).

221156992 is an abundant number, since it is smaller than the sum of its proper divisors (305765828).

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

221156992 is an equidigital number, since it uses as much as digits as its factorization.

221156992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1018 (or 999 counting only the distinct ones).

The product of its digits is 19440, while the sum is 37.

The square root of 221156992 is about 14871.3480222877. The cubic root of 221156992 is about 604.7374878234.

The spelling of 221156992 in words is "two hundred twenty-one million, one hundred fifty-six thousand, nine hundred ninety-two".