21143142997 has 2 divisors, whose sum is σ = 21143142998. Its totient is φ = 21143142996.

The previous prime is 21143142983. The next prime is 21143143027. The reversal of 21143142997 is 79924134112.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 14851321956 + 6291821041 = 121866^2 + 79321^2 .

It is a cyclic number.

It is not a de Polignac number, because 21143142997 - 2¹⁵ = 21143110229 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21143142907) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10571571498 + 10571571499.

It is an arithmetic number, because the mean of its divisors is an integer number (10571571499).

Almost surely, 2^21143142997 is an apocalyptic number.

It is an amenable number.

21143142997 is a deficient number, since it is larger than the sum of its proper divisors (1).

21143142997 is an equidigital number, since it uses as much as digits as its factorization.

21143142997 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 108864, while the sum is 43.

The spelling of 21143142997 in words is "twenty-one billion, one hundred forty-three million, one hundred forty-two thousand, nine hundred ninety-seven".