126821381 has 2 divisors, whose sum is σ = 126821382. Its totient is φ = 126821380.

The previous prime is 126821363. The next prime is 126821399. The reversal of 126821381 is 183128621.

It is a balanced prime because it is at equal distance from previous prime (126821363) and next prime (126821399).

It can be written as a sum of positive squares in only one way, i.e., 123432100 + 3389281 = 11110^2 + 1841^2 .

It is a cyclic number.

It is not a de Polignac number, because 126821381 - 2²² = 122627077 is a prime.

It is a super-2 number, since 2×126821381² = 32167325357494322, which contains 22 as substring.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (126821281) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 63410690 + 63410691.

It is an arithmetic number, because the mean of its divisors is an integer number (63410691).

Almost surely, 2^126821381 is an apocalyptic number.

It is an amenable number.

126821381 is a deficient number, since it is larger than the sum of its proper divisors (1).

126821381 is an equidigital number, since it uses as much as digits as its factorization.

126821381 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4608, while the sum is 32.

The square root of 126821381 is about 11261.4999445012. The cubic root of 126821381 is about 502.4168072633.

The spelling of 126821381 in words is "one hundred twenty-six million, eight hundred twenty-one thousand, three hundred eighty-one".