21213612523253 has 2 divisors, whose sum is σ = 21213612523254. Its totient is φ = 21213612523252.

The previous prime is 21213612523237. The next prime is 21213612523261. The reversal of 21213612523253 is 35232521631212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20695202443204 + 518410080049 = 4549198^2 + 720007^2 .

It is a cyclic number.

It is not a de Polignac number, because 21213612523253 - 2⁴ = 21213612523237 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21213612523853) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606806261626 + 10606806261627.

It is an arithmetic number, because the mean of its divisors is an integer number (10606806261627).

Almost surely, 2^{21213612523253} is an apocalyptic number.

It is an amenable number.

21213612523253 is a deficient number, since it is larger than the sum of its proper divisors (1).

21213612523253 is an equidigital number, since it uses as much as digits as its factorization.

21213612523253 is an evil number, because the sum of its binary digits is even.

The product of its digits is 129600, while the sum is 38.

The spelling of 21213612523253 in words is "twenty-one trillion, two hundred thirteen billion, six hundred twelve million, five hundred twenty-three thousand, two hundred fifty-three".