75381621 has 16 divisors (see below), whose sum is σ = 121624704. Its totient is φ = 40541184.

The previous prime is 75381619. The next prime is 75381637. The reversal of 75381621 is 12618357.

It is not a de Polignac number, because 75381621 - 2¹ = 75381619 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (75381641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 105220 + ... + 105933.

It is an arithmetic number, because the mean of its divisors is an integer number (7601544).

Almost surely, 2^75381621 is an apocalyptic number.

It is an amenable number.

75381621 is a deficient number, since it is larger than the sum of its proper divisors (46243083).

75381621 is a wasteful number, since it uses less digits than its factorization.

75381621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 211180.

The product of its digits is 10080, while the sum is 33.

The square root of 75381621 is about 8682.2589802424. The cubic root of 75381621 is about 422.4303931639.

Adding to 75381621 its reverse (12618357), we get a palindrome (87999978).

The spelling of 75381621 in words is "seventy-five million, three hundred eighty-one thousand, six hundred twenty-one".