21323120149 has 2 divisors, whose sum is σ = 21323120150. Its totient is φ = 21323120148.

The previous prime is 21323120107. The next prime is 21323120171. The reversal of 21323120149 is 94102132312.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17228400049 + 4094720100 = 131257^2 + 63990^2 .

It is a cyclic number.

It is not a de Polignac number, because 21323120149 - 2¹¹ = 21323118101 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21323120449) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10661560074 + 10661560075.

It is an arithmetic number, because the mean of its divisors is an integer number (10661560075).

Almost surely, 2^21323120149 is an apocalyptic number.

It is an amenable number.

21323120149 is a deficient number, since it is larger than the sum of its proper divisors (1).

21323120149 is an equidigital number, since it uses as much as digits as its factorization.

21323120149 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2592, while the sum is 28.

The spelling of 21323120149 in words is "twenty-one billion, three hundred twenty-three million, one hundred twenty thousand, one hundred forty-nine".