136998821 has 2 divisors, whose sum is σ = 136998822. Its totient is φ = 136998820.

The previous prime is 136998809. The next prime is 136998839. The reversal of 136998821 is 128899631.

136998821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 127938721 + 9060100 = 11311^2 + 3010^2 .

It is a cyclic number.

It is not a de Polignac number, because 136998821 - 2¹⁴ = 136982437 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (136998221) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 68499410 + 68499411.

It is an arithmetic number, because the mean of its divisors is an integer number (68499411).

Almost surely, 2^136998821 is an apocalyptic number.

It is an amenable number.

136998821 is a deficient number, since it is larger than the sum of its proper divisors (1).

136998821 is an equidigital number, since it uses as much as digits as its factorization.

136998821 is an evil number, because the sum of its binary digits is even.

The product of its digits is 186624, while the sum is 47.

The square root of 136998821 is about 11704.6495462273. The cubic root of 136998821 is about 515.5121947340.

The spelling of 136998821 in words is "one hundred thirty-six million, nine hundred ninety-eight thousand, eight hundred twenty-one".