75221021 has 8 divisors (see below), whose sum is σ = 76624704. Its totient is φ = 73827040.

The previous prime is 75220997. The next prime is 75221033. The reversal of 75221021 is 12012257.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-75221021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 75220984 and 75221002.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (75221071) 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, 14270 + ... + 18816.

It is an arithmetic number, because the mean of its divisors is an integer number (9578088).

Almost surely, 2^75221021 is an apocalyptic number.

75221021 is a gapful number since it is divisible by the number (71) formed by its first and last digit.

It is an amenable number.

75221021 is a deficient number, since it is larger than the sum of its proper divisors (1403683).

75221021 is a wasteful number, since it uses less digits than its factorization.

75221021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4851.

The product of its (nonzero) digits is 280, while the sum is 20.

The square root of 75221021 is about 8673.0053038148. The cubic root of 75221021 is about 422.1301848968.

Adding to 75221021 its reverse (12012257), we get a palindrome (87233278).

The spelling of 75221021 in words is "seventy-five million, two hundred twenty-one thousand, twenty-one".