101640251 has 2 divisors, whose sum is σ = 101640252. Its totient is φ = 101640250.

The previous prime is 101640193. The next prime is 101640257. The reversal of 101640251 is 152046101.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-101640251 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (101640257) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50820125 + 50820126.

It is an arithmetic number, because the mean of its divisors is an integer number (50820126).

Almost surely, 2^101640251 is an apocalyptic number.

101640251 is a deficient number, since it is larger than the sum of its proper divisors (1).

101640251 is an equidigital number, since it uses as much as digits as its factorization.

101640251 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 101640251 is about 10081.6789772339. The cubic root of 101640251 is about 466.6829232999.

Adding to 101640251 its reverse (152046101), we get a palindrome (253686352).

The spelling of 101640251 in words is "one hundred one million, six hundred forty thousand, two hundred fifty-one".