221631696 has 240 divisors, whose sum is σ = 747452160. Its totient is φ = 60410880.

The previous prime is 221631653. The next prime is 221631701. The reversal of 221631696 is 696136122.

It is a happy number.

221631696 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a nude number because it is divisible by every one of its digits.

It is a self number, because there is not a number n which added to its sum of digits gives 221631696.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 967710 + ... + 967938.

It is an arithmetic number, because the mean of its divisors is an integer number (3114384).

Almost surely, 2^221631696 is an apocalyptic number.

221631696 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 221631696, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (373726080).

221631696 is an abundant number, since it is smaller than the sum of its proper divisors (525820464).

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

221631696 is a wasteful number, since it uses less digits than its factorization.

221631696 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 314 (or 305 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 221631696 is about 14887.2998223318. The cubic root of 221631696 is about 605.1698596436.

The spelling of 221631696 in words is "two hundred twenty-one million, six hundred thirty-one thousand, six hundred ninety-six".