216025021 has 8 divisors (see below), whose sum is σ = 217736064. Its totient is φ = 214319280.

The previous prime is 216025009. The next prime is 216025049. The reversal of 216025021 is 120520612.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 216025021 - 2⁵ = 216024989 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 216025021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (216925021) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 123211 + ... + 124951.

It is an arithmetic number, because the mean of its divisors is an integer number (27217008).

Almost surely, 2^216025021 is an apocalyptic number.

It is an amenable number.

216025021 is a deficient number, since it is larger than the sum of its proper divisors (1711043).

216025021 is a wasteful number, since it uses less digits than its factorization.

216025021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2651.

The product of its (nonzero) digits is 240, while the sum is 19.

The square root of 216025021 is about 14697.7896637556. The cubic root of 216025021 is about 600.0231666981.

Adding to 216025021 its reverse (120520612), we get a palindrome (336545633).

The spelling of 216025021 in words is "two hundred sixteen million, twenty-five thousand, twenty-one".