100721507 has 2 divisors, whose sum is σ = 100721508. Its totient is φ = 100721506.

The previous prime is 100721503. The next prime is 100721521. The reversal of 100721507 is 705127001.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 100721507 - 2² = 100721503 is a prime.

It is not a weakly prime, because it can be changed into another prime (100721501) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50360753 + 50360754.

It is an arithmetic number, because the mean of its divisors is an integer number (50360754).

Almost surely, 2^100721507 is an apocalyptic number.

100721507 is a deficient number, since it is larger than the sum of its proper divisors (1).

100721507 is an equidigital number, since it uses as much as digits as its factorization.

100721507 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 490, while the sum is 23.

The square root of 100721507 is about 10036.0105121507. The cubic root of 100721507 is about 465.2725222575.

Adding to 100721507 its reverse (705127001), we get a palindrome (805848508).

The spelling of 100721507 in words is "one hundred million, seven hundred twenty-one thousand, five hundred seven".