21302012121 has 24 divisors (see below), whose sum is σ = 31335901056. Its totient is φ = 12861576000.

The previous prime is 21302012063. The next prime is 21302012131. The reversal of 21302012121 is 12121020312.

It is not a de Polignac number, because 21302012121 - 2⁶ = 21302012057 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21302012121.

It is not an unprimeable number, because it can be changed into a prime (21302012131) 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, 369505 + ... + 423246.

It is an arithmetic number, because the mean of its divisors is an integer number (1305662544).

Almost surely, 2^21302012121 is an apocalyptic number.

It is an amenable number.

21302012121 is a deficient number, since it is larger than the sum of its proper divisors (10033888935).

21302012121 is a wasteful number, since it uses less digits than its factorization.

21302012121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 792833 (or 792820 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 21302012121 its reverse (12121020312), we get a palindrome (33423032433).

The spelling of 21302012121 in words is "twenty-one billion, three hundred two million, twelve thousand, one hundred twenty-one".