106421257 has 2 divisors, whose sum is σ = 106421258. Its totient is φ = 106421256.

The previous prime is 106421221. The next prime is 106421279. The reversal of 106421257 is 752124601.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 87965641 + 18455616 = 9379^2 + 4296^2 .

It is an emirp because it is prime and its reverse (752124601) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 106421257 - 2¹⁵ = 106388489 is a prime.

It is a super-2 number, since 2×106421257² = 22650967882920098, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (106421057) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 53210628 + 53210629.

It is an arithmetic number, because the mean of its divisors is an integer number (53210629).

Almost surely, 2^106421257 is an apocalyptic number.

It is an amenable number.

106421257 is a deficient number, since it is larger than the sum of its proper divisors (1).

106421257 is an equidigital number, since it uses as much as digits as its factorization.

106421257 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3360, while the sum is 28.

The square root of 106421257 is about 10316.0679040030. The cubic root of 106421257 is about 473.8884546463. Note that the first 3 decimals are identical.

Adding to 106421257 its reverse (752124601), we get a palindrome (858545858).

The spelling of 106421257 in words is "one hundred six million, four hundred twenty-one thousand, two hundred fifty-seven".