216221425 has 24 divisors (see below), whose sum is σ = 322548800. Its totient is φ = 140460480.

The previous prime is 216221417. The next prime is 216221429. The reversal of 216221425 is 524122612.

It is not a de Polignac number, because 216221425 - 2³ = 216221417 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a self number, because there is not a number n which added to its sum of digits gives 216221425.

It is not an unprimeable number, because it can be changed into a prime (216221429) 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, 29190 + ... + 35839.

Almost surely, 2^216221425 is an apocalyptic number.

216221425 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

216221425 is a deficient number, since it is larger than the sum of its proper divisors (106327375).

216221425 is a wasteful number, since it uses less digits than its factorization.

216221425 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 65065 (or 65060 counting only the distinct ones).

The product of its digits is 1920, while the sum is 25.

The square root of 216221425 is about 14704.4695586070. The cubic root of 216221425 is about 600.2049531305.

The spelling of 216221425 in words is "two hundred sixteen million, two hundred twenty-one thousand, four hundred twenty-five".