21149068949 has 2 divisors, whose sum is σ = 21149068950. Its totient is φ = 21149068948.

The previous prime is 21149068937. The next prime is 21149068957. The reversal of 21149068949 is 94986094112.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20522568049 + 626500900 = 143257^2 + 25030^2 .

It is a cyclic number.

It is not a de Polignac number, because 21149068949 - 2⁴ = 21149068933 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21149068949.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21149068979) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10574534474 + 10574534475.

It is an arithmetic number, because the mean of its divisors is an integer number (10574534475).

Almost surely, 2^21149068949 is an apocalyptic number.

It is an amenable number.

21149068949 is a deficient number, since it is larger than the sum of its proper divisors (1).

21149068949 is an equidigital number, since it uses as much as digits as its factorization.

21149068949 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1119744, while the sum is 53.

The spelling of 21149068949 in words is "twenty-one billion, one hundred forty-nine million, sixty-eight thousand, nine hundred forty-nine".