214961821 has 16 divisors (see below), whose sum is σ = 230997744. Its totient is φ = 199327744.

The previous prime is 214961819. The next prime is 214961837. The reversal of 214961821 is 128169412.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 49196196 + 165765625 = 7014^2 + 12875^2 .

It is a cyclic number.

It is not a de Polignac number, because 214961821 - 2¹ = 214961819 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (214961881) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 608781 + ... + 609133.

It is an arithmetic number, because the mean of its divisors is an integer number (14437359).

Almost surely, 2^214961821 is an apocalyptic number.

It is an amenable number.

214961821 is a deficient number, since it is larger than the sum of its proper divisors (16035923).

214961821 is a wasteful number, since it uses less digits than its factorization.

214961821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 800.

The product of its digits is 6912, while the sum is 34.

The square root of 214961821 is about 14661.5763477192. The cubic root of 214961821 is about 599.0371789339.

The spelling of 214961821 in words is "two hundred fourteen million, nine hundred sixty-one thousand, eight hundred twenty-one".