20402437949 has 2 divisors, whose sum is σ = 20402437950. Its totient is φ = 20402437948.

The previous prime is 20402437903. The next prime is 20402437969. The reversal of 20402437949 is 94973420402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20169112324 + 233325625 = 142018^2 + 15275^2 .

It is a cyclic number.

It is not a de Polignac number, because 20402437949 - 2¹² = 20402433853 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20402437969) 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, 10201218974 + 10201218975.

It is an arithmetic number, because the mean of its divisors is an integer number (10201218975).

Almost surely, 2^20402437949 is an apocalyptic number.

It is an amenable number.

20402437949 is a deficient number, since it is larger than the sum of its proper divisors (1).

20402437949 is an equidigital number, since it uses as much as digits as its factorization.

20402437949 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 435456, while the sum is 44.

The spelling of 20402437949 in words is "twenty billion, four hundred two million, four hundred thirty-seven thousand, nine hundred forty-nine".