75658553721 has 27 divisors (see below), whose sum is σ = 110012893263. Its totient is φ = 50105111760.

The previous prime is 75658553713. The next prime is 75658553723. The reversal of 75658553721 is 12735585657.

The square root of 75658553721 is 275061.

It is a perfect power (a square), and thus also a powerful number.

75658553721 is a `hidden beast` number, since 7 + 5 + 6 + 5 + 85 + 537 + 21 = 666.

It can be written as a sum of positive squares in only one way, i.e., 13040498025 + 62618055696 = 114195^2 + 250236^2 .

It is not a de Polignac number, because 75658553721 - 2³ = 75658553713 is a prime.

It is a super-3 number, since 3×75658553721³ (a number of 34 digits) contains 333 as substring.

It is not an unprimeable number, because it can be changed into a prime (75658553723) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 228575526 + ... + 228575856.

Almost surely, 2^75658553721 is an apocalyptic number.

75658553721 is the 275061-st square number.

75658553721 is the 137531-st centered octagonal number.

It is an amenable number.

75658553721 is a deficient number, since it is larger than the sum of its proper divisors (34354339542).

75658553721 is an frugal number, since it uses more digits than its factorization.

75658553721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1222 (or 611 counting only the distinct ones).

The product of its digits is 8820000, while the sum is 54.

The spelling of 75658553721 in words is "seventy-five billion, six hundred fifty-eight million, five hundred fifty-three thousand, seven hundred twenty-one".