78253586048521 has 16 divisors (see below), whose sum is σ = 84954261268800. Its totient is φ = 71650712352960.

The previous prime is 78253586048479. The next prime is 78253586048633. The reversal of 78253586048521 is 12584068535287.

It is a happy number.

It is not a de Polignac number, because 78253586048521 - 2⁹ = 78253586048009 is a prime.

It is a super-2 number, since 2×78253586048521² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (78253586048021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6423246 + ... + 14062903.

It is an arithmetic number, because the mean of its divisors is an integer number (5309641329300).

Almost surely, 2^{78253586048521} is an apocalyptic number.

It is an amenable number.

78253586048521 is a deficient number, since it is larger than the sum of its proper divisors (6700675220279).

78253586048521 is a wasteful number, since it uses less digits than its factorization.

78253586048521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20488536.

The product of its (nonzero) digits is 129024000, while the sum is 64.

The spelling of 78253586048521 in words is "seventy-eight trillion, two hundred fifty-three billion, five hundred eighty-six million, forty-eight thousand, five hundred twenty-one".