21242545430250 has 64 divisors (see below), whose sum is σ = 55326671412480. Its totient is φ = 5418388395200.

The previous prime is 21242545430243. The next prime is 21242545430257. The reversal of 21242545430250 is 5203454524212.

It is an interprime number because it is at equal distance from previous prime (21242545430243) and next prime (21242545430257).

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21242545430199 and 21242545430208.

It is not an unprimeable number, because it can be changed into a prime (21242545430257) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 615708705 + ... + 615743204.

It is an arithmetic number, because the mean of its divisors is an integer number (864479240820).

Almost surely, 2^{21242545430250} is an apocalyptic number.

21242545430250 is an abundant number, since it is smaller than the sum of its proper divisors (34084125982230).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21242545430250 is a wasteful number, since it uses less digits than its factorization.

21242545430250 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1231451952 (or 1231451942 counting only the distinct ones).

The product of its (nonzero) digits is 384000, while the sum is 39.

Adding to 21242545430250 its reverse (5203454524212), we get a palindrome (26445999954462).

The spelling of 21242545430250 in words is "twenty-one trillion, two hundred forty-two billion, five hundred forty-five million, four hundred thirty thousand, two hundred fifty".