72530755642421 has 4 divisors (see below), whose sum is σ = 73345707953100. Its totient is φ = 71715803331744.

The previous prime is 72530755642381. The next prime is 72530755642441. The reversal of 72530755642421 is 12424655703527.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 33347287133521 + 39183468508900 = 5774711^2 + 6259670^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-72530755642421 is a prime.

It is a super-3 number, since 3×72530755642421³ (a number of 43 digits) contains 333 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 (72530755642441) 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, 407476155206 + ... + 407476155383.

It is an arithmetic number, because the mean of its divisors is an integer number (18336426988275).

Almost surely, 2^{72530755642421} is an apocalyptic number.

It is an amenable number.

72530755642421 is a deficient number, since it is larger than the sum of its proper divisors (814952310679).

72530755642421 is an equidigital number, since it uses as much as digits as its factorization.

72530755642421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 814952310678.

The product of its (nonzero) digits is 14112000, while the sum is 53.

The spelling of 72530755642421 in words is "seventy-two trillion, five hundred thirty billion, seven hundred fifty-five million, six hundred forty-two thousand, four hundred twenty-one".