20861333149 has 2 divisors, whose sum is σ = 20861333150. Its totient is φ = 20861333148.

The previous prime is 20861333113. The next prime is 20861333189. The reversal of 20861333149 is 94133316802.

It is a happy number.

It is an a-pointer prime, because the next prime (20861333189) can be obtained adding 20861333149 to its sum of digits (40).

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18411776100 + 2449557049 = 135690^2 + 49493^2 .

It is a cyclic number.

It is not a de Polignac number, because 20861333149 - 2¹⁵ = 20861300381 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20861333189) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10430666574 + 10430666575.

It is an arithmetic number, because the mean of its divisors is an integer number (10430666575).

Almost surely, 2^20861333149 is an apocalyptic number.

It is an amenable number.

20861333149 is a deficient number, since it is larger than the sum of its proper divisors (1).

20861333149 is an equidigital number, since it uses as much as digits as its factorization.

20861333149 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 93312, while the sum is 40.

The spelling of 20861333149 in words is "twenty billion, eight hundred sixty-one million, three hundred thirty-three thousand, one hundred forty-nine".