136421352257 has 2 divisors, whose sum is σ = 136421352258. Its totient is φ = 136421352256.

The previous prime is 136421352239. The next prime is 136421352299. The reversal of 136421352257 is 752253124631.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 73030198081 + 63391154176 = 270241^2 + 251776^2 .

It is a cyclic number.

It is not a de Polignac number, because 136421352257 - 2¹⁰ = 136421351233 is a prime.

It is a super-2 number, since 2×136421352257² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (136421352217) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 68210676128 + 68210676129.

It is an arithmetic number, because the mean of its divisors is an integer number (68210676129).

Almost surely, 2^136421352257 is an apocalyptic number.

It is an amenable number.

136421352257 is a deficient number, since it is larger than the sum of its proper divisors (1).

136421352257 is an equidigital number, since it uses as much as digits as its factorization.

136421352257 is an evil number, because the sum of its binary digits is even.

The product of its digits is 302400, while the sum is 41.

Adding to 136421352257 its reverse (752253124631), we get a palindrome (888674476888).

The spelling of 136421352257 in words is "one hundred thirty-six billion, four hundred twenty-one million, three hundred fifty-two thousand, two hundred fifty-seven".