21225030165 has 96 divisors (see below), whose sum is σ = 38253720960. Its totient is φ = 10881497088.

The previous prime is 21225030143. The next prime is 21225030181. The reversal of 21225030165 is 56103052212.

It is a happy number.

It is not a de Polignac number, because 21225030165 - 2⁵ = 21225030133 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 22271329 + ... + 22272281.

It is an arithmetic number, because the mean of its divisors is an integer number (398476260).

Almost surely, 2^21225030165 is an apocalyptic number.

It is an amenable number.

21225030165 is a deficient number, since it is larger than the sum of its proper divisors (17028690795).

21225030165 is a wasteful number, since it uses less digits than its factorization.

21225030165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1203 (or 1200 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 27.

Adding to 21225030165 its reverse (56103052212), we get a palindrome (77328082377).

The spelling of 21225030165 in words is "twenty-one billion, two hundred twenty-five million, thirty thousand, one hundred sixty-five".