75550421 has 4 divisors (see below), whose sum is σ = 75726144. Its totient is φ = 75374700.

The previous prime is 75550417. The next prime is 75550439. The reversal of 75550421 is 12405557.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 75550421 - 2² = 75550417 is a prime.

It is a super-2 number, since 2×75550421² = 11415732226554482, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (75556421) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 87215 + ... + 88076.

It is an arithmetic number, because the mean of its divisors is an integer number (18931536).

Almost surely, 2^75550421 is an apocalyptic number.

It is an amenable number.

75550421 is a deficient number, since it is larger than the sum of its proper divisors (175723).

75550421 is a wasteful number, since it uses less digits than its factorization.

75550421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 175722.

The product of its (nonzero) digits is 7000, while the sum is 29.

The square root of 75550421 is about 8691.9745167597. The cubic root of 75550421 is about 422.7454703707.

Adding to 75550421 its reverse (12405557), we get a palindrome (87955978).

The spelling of 75550421 in words is "seventy-five million, five hundred fifty thousand, four hundred twenty-one".