77721326543 has 4 divisors (see below), whose sum is σ = 88824373200. Its totient is φ = 66618279888.

The previous prime is 77721326503. The next prime is 77721326569. The reversal of 77721326543 is 34562312777.

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

It is a cyclic number.

It is not a de Polignac number, because 77721326543 - 2¹⁰ = 77721325519 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (77721326503) 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, 5551523318 + ... + 5551523331.

It is an arithmetic number, because the mean of its divisors is an integer number (22206093300).

Almost surely, 2^77721326543 is an apocalyptic number.

77721326543 is a deficient number, since it is larger than the sum of its proper divisors (11103046657).

77721326543 is a wasteful number, since it uses less digits than its factorization.

77721326543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11103046656.

The product of its digits is 1481760, while the sum is 47.

The spelling of 77721326543 in words is "seventy-seven billion, seven hundred twenty-one million, three hundred twenty-six thousand, five hundred forty-three".