21030405320251 has 8 divisors (see below), whose sum is σ = 21708858225024. Its totient is φ = 20351955711360.

The previous prime is 21030405320231. The next prime is 21030405320263. The reversal of 21030405320251 is 15202350403012.

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 21030405320251 - 2⁵ = 21030405320219 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21030405320231) 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, 24425091 + ... + 25271443.

It is an arithmetic number, because the mean of its divisors is an integer number (2713607278128).

Almost surely, 2^{21030405320251} is an apocalyptic number.

21030405320251 is a deficient number, since it is larger than the sum of its proper divisors (678452904773).

21030405320251 is an equidigital number, since it uses as much as digits as its factorization.

21030405320251 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1647941.

The product of its (nonzero) digits is 7200, while the sum is 28.

Adding to 21030405320251 its reverse (15202350403012), we get a palindrome (36232755723263).

The spelling of 21030405320251 in words is "twenty-one trillion, thirty billion, four hundred five million, three hundred twenty thousand, two hundred fifty-one".