75147198521 has 4 divisors (see below), whose sum is σ = 75213760500. Its totient is φ = 75080636544.

The previous prime is 75147198517. The next prime is 75147198583. The reversal of 75147198521 is 12589174157.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12589174157 = 7 ⋅1798453451.

It can be written as a sum of positive squares in 2 ways, for example, as 3610207225 + 71536991296 = 60085^2 + 267464^2 .

It is a cyclic number.

It is not a de Polignac number, because 75147198521 - 2² = 75147198517 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 75147198521.

It is not an unprimeable number, because it can be changed into a prime (75147198221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33279296 + ... + 33281553.

It is an arithmetic number, because the mean of its divisors is an integer number (18803440125).

Almost surely, 2^75147198521 is an apocalyptic number.

It is an amenable number.

75147198521 is a deficient number, since it is larger than the sum of its proper divisors (66561979).

75147198521 is a wasteful number, since it uses less digits than its factorization.

75147198521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 66561978.

The product of its digits is 705600, while the sum is 50.

The spelling of 75147198521 in words is "seventy-five billion, one hundred forty-seven million, one hundred ninety-eight thousand, five hundred twenty-one".