84065912521 has 4 divisors (see below), whose sum is σ = 84067165312. Its totient is φ = 84064659732.

The previous prime is 84065912459. The next prime is 84065912531. The reversal of 84065912521 is 12521956048.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 84065912521 - 2¹⁹ = 84065388233 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (84065912531) 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, 519681 + ... + 661966.

It is an arithmetic number, because the mean of its divisors is an integer number (21016791328).

Almost surely, 2^84065912521 is an apocalyptic number.

It is an amenable number.

84065912521 is a deficient number, since it is larger than the sum of its proper divisors (1252791).

84065912521 is a wasteful number, since it uses less digits than its factorization.

84065912521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1252790.

The product of its (nonzero) digits is 172800, while the sum is 43.

The spelling of 84065912521 in words is "eighty-four billion, sixty-five million, nine hundred twelve thousand, five hundred twenty-one".