21142332309947 has 2 divisors, whose sum is σ = 21142332309948. Its totient is φ = 21142332309946.

The previous prime is 21142332309899. The next prime is 21142332310031. The reversal of 21142332309947 is 74990323324112.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21142332309947 - 2⁶ = 21142332309883 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21142332309895 and 21142332309904.

It is not a weakly prime, because it can be changed into another prime (21142332309647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10571166154973 + 10571166154974.

It is an arithmetic number, because the mean of its divisors is an integer number (10571166154974).

Almost surely, 2^{21142332309947} is an apocalyptic number.

21142332309947 is a deficient number, since it is larger than the sum of its proper divisors (1).

21142332309947 is an equidigital number, since it uses as much as digits as its factorization.

21142332309947 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1959552, while the sum is 50.

The spelling of 21142332309947 in words is "twenty-one trillion, one hundred forty-two billion, three hundred thirty-two million, three hundred nine thousand, nine hundred forty-seven".