221940825 has 24 divisors (see below), whose sum is σ = 368282976. Its totient is φ = 117936000.

The previous prime is 221940821. The next prime is 221940827. The reversal of 221940825 is 528049122.

221940825 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 221940825 - 2² = 221940821 is a prime.

It is not an unprimeable number, because it can be changed into a prime (221940821) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 15810 + ... + 26340.

It is an arithmetic number, because the mean of its divisors is an integer number (15345124).

Almost surely, 2^221940825 is an apocalyptic number.

221940825 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

221940825 is a deficient number, since it is larger than the sum of its proper divisors (146342151).

221940825 is a wasteful number, since it uses less digits than its factorization.

221940825 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10825 (or 10820 counting only the distinct ones).

The product of its (nonzero) digits is 11520, while the sum is 33.

The square root of 221940825 is about 14897.6785104257. The cubic root of 221940825 is about 605.4510899421.

Adding to 221940825 its reverse (528049122), we get a palindrome (749989947).

The spelling of 221940825 in words is "two hundred twenty-one million, nine hundred forty thousand, eight hundred twenty-five".