6973856521 has 4 divisors (see below), whose sum is σ = 6974023552. Its totient is φ = 6973689492.

The previous prime is 6973856497. The next prime is 6973856567. The reversal of 6973856521 is 1256583796.

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, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6973856521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6973856821) 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, 40336 + ... + 124798.

It is an arithmetic number, because the mean of its divisors is an integer number (1743505888).

Almost surely, 2^6973856521 is an apocalyptic number.

It is an amenable number.

6973856521 is a deficient number, since it is larger than the sum of its proper divisors (167031).

6973856521 is an equidigital number, since it uses as much as digits as its factorization.

6973856521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 167030.

The product of its digits is 2721600, while the sum is 52.

The square root of 6973856521 is about 83509.6193321464. The cubic root of 6973856521 is about 1910.5467510877.

The spelling of 6973856521 in words is "six billion, nine hundred seventy-three million, eight hundred fifty-six thousand, five hundred twenty-one".