21502550243297 has 12 divisors (see below), whose sum is σ = 22478722588224. Its totient is φ = 20567079098280.

The previous prime is 21502550243287. The next prime is 21502550243347. The reversal of 21502550243297 is 79234205520512.

It is not a de Polignac number, because 21502550243297 - 2¹² = 21502550239201 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21502550243227) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 18910028 + ... + 20014850.

It is an arithmetic number, because the mean of its divisors is an integer number (1873226882352).

Almost surely, 2^{21502550243297} is an apocalyptic number.

It is an amenable number.

21502550243297 is a deficient number, since it is larger than the sum of its proper divisors (976172344927).

21502550243297 is a wasteful number, since it uses less digits than its factorization.

21502550243297 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1141660 (or 1141637 counting only the distinct ones).

The product of its (nonzero) digits is 1512000, while the sum is 47.

The spelling of 21502550243297 in words is "twenty-one trillion, five hundred two billion, five hundred fifty million, two hundred forty-three thousand, two hundred ninety-seven".