75644021 has 8 divisors (see below), whose sum is σ = 77804544. Its totient is φ = 73489680.

The previous prime is 75644003. The next prime is 75644029. The reversal of 75644021 is 12044657.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 75644021 - 2⁶ = 75643957 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (75644029) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 35636 + ... + 37698.

It is an arithmetic number, because the mean of its divisors is an integer number (9725568).

Almost surely, 2^75644021 is an apocalyptic number.

It is an amenable number.

75644021 is a deficient number, since it is larger than the sum of its proper divisors (2160523).

75644021 is a wasteful number, since it uses less digits than its factorization.

75644021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3091.

The product of its (nonzero) digits is 6720, while the sum is 29.

The square root of 75644021 is about 8697.3571273117. The cubic root of 75644021 is about 422.9199791997.

Adding to 75644021 its reverse (12044657), we get a palindrome (87688678).

The spelling of 75644021 in words is "seventy-five million, six hundred forty-four thousand, twenty-one".