2215523421 has 20 divisors (see below), whose sum is σ = 3325320064. Its totient is φ = 1470004200.

The previous prime is 2215523389. The next prime is 2215523423. The reversal of 2215523421 is 1243255122.

2215523421 is a `hidden beast` number, since 2 + 215 + 5 + 23 + 421 = 666.

It is not a de Polignac number, because 2215523421 - 2⁵ = 2215523389 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2215523423) 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 19 ways as a sum of consecutive naturals, for example, 47725 + ... + 81906.

Almost surely, 2^2215523421 is an apocalyptic number.

It is an amenable number.

2215523421 is a deficient number, since it is larger than the sum of its proper divisors (1109796643).

2215523421 is a wasteful number, since it uses less digits than its factorization.

2215523421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 129854 (or 129845 counting only the distinct ones).

The product of its digits is 4800, while the sum is 27.

The square root of 2215523421 is about 47069.3469361962. The cubic root of 2215523421 is about 1303.6433146052.

Adding to 2215523421 its reverse (1243255122), we get a palindrome (3458778543).

The spelling of 2215523421 in words is "two billion, two hundred fifteen million, five hundred twenty-three thousand, four hundred twenty-one".