6421266157 has 2 divisors, whose sum is σ = 6421266158. Its totient is φ = 6421266156.

The previous prime is 6421266149. The next prime is 6421266211. The reversal of 6421266157 is 7516621246.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6255860836 + 165405321 = 79094^2 + 12861^2 .

It is a cyclic number.

It is not a de Polignac number, because 6421266157 - 2³ = 6421266149 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6421266107) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3210633078 + 3210633079.

It is an arithmetic number, because the mean of its divisors is an integer number (3210633079).

Almost surely, 2^6421266157 is an apocalyptic number.

It is an amenable number.

6421266157 is a deficient number, since it is larger than the sum of its proper divisors (1).

6421266157 is an equidigital number, since it uses as much as digits as its factorization.

6421266157 is an evil number, because the sum of its binary digits is even.

The product of its digits is 120960, while the sum is 40.

The square root of 6421266157 is about 80132.8032518519. The cubic root of 6421266157 is about 1858.6896923453.

The spelling of 6421266157 in words is "six billion, four hundred twenty-one million, two hundred sixty-six thousand, one hundred fifty-seven".