66401075 has 12 divisors (see below), whose sum is σ = 88671408. Its totient is φ = 49034400.

The previous prime is 66401063. The next prime is 66401077. The reversal of 66401075 is 57010466.

It is not a de Polignac number, because 66401075 - 2⁶ = 66401011 is a prime.

It is a super-2 number, since 2×66401075² = 8818205522311250, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (66401077) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 101831 + ... + 102480.

It is an arithmetic number, because the mean of its divisors is an integer number (7389284).

Almost surely, 2^66401075 is an apocalyptic number.

66401075 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

66401075 is a deficient number, since it is larger than the sum of its proper divisors (22270333).

66401075 is a wasteful number, since it uses less digits than its factorization.

66401075 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 204334 (or 204329 counting only the distinct ones).

The product of its (nonzero) digits is 5040, while the sum is 29.

The square root of 66401075 is about 8148.6854768116. The cubic root of 66401075 is about 404.9409556763.

The spelling of 66401075 in words is "sixty-six million, four hundred one thousand, seventy-five".