1236820229 has 2 divisors, whose sum is σ = 1236820230. Its totient is φ = 1236820228.

The previous prime is 1236820199. The next prime is 1236820231. The reversal of 1236820229 is 9220286321.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1231869604 + 4950625 = 35098^2 + 2225^2 .

It is a cyclic number.

It is not a de Polignac number, because 1236820229 - 2¹⁶ = 1236754693 is a prime.

It is a super-2 number, since 2×1236820229² = 3059448557727224882, which contains 22 as substring.

Together with 1236820231, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1236820279) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 618410114 + 618410115.

It is an arithmetic number, because the mean of its divisors is an integer number (618410115).

Almost surely, 2^1236820229 is an apocalyptic number.

It is an amenable number.

1236820229 is a deficient number, since it is larger than the sum of its proper divisors (1).

1236820229 is an equidigital number, since it uses as much as digits as its factorization.

1236820229 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20736, while the sum is 35.

The square root of 1236820229 is about 35168.4550271973. The cubic root of 1236820229 is about 1073.4179661306.

The spelling of 1236820229 in words is "one billion, two hundred thirty-six million, eight hundred twenty thousand, two hundred twenty-nine".