100661401 has 2 divisors, whose sum is σ = 100661402. Its totient is φ = 100661400.

The previous prime is 100661399. The next prime is 100661413. The reversal of 100661401 is 104166001.

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., 98485776 + 2175625 = 9924^2 + 1475^2 .

It is an emirp because it is prime and its reverse (104166001) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 100661401 - 2¹ = 100661399 is a prime.

Together with 100661399, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (100661441) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50330700 + 50330701.

It is an arithmetic number, because the mean of its divisors is an integer number (50330701).

Almost surely, 2^100661401 is an apocalyptic number.

It is an amenable number.

100661401 is a deficient number, since it is larger than the sum of its proper divisors (1).

100661401 is an equidigital number, since it uses as much as digits as its factorization.

100661401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 19.

The square root of 100661401 is about 10033.0155486773. The cubic root of 100661401 is about 465.1799527035.

The spelling of 100661401 in words is "one hundred million, six hundred sixty-one thousand, four hundred one".