77531045821 has 8 divisors (see below), whose sum is σ = 81633812000. Its totient is φ = 73430498160.

The previous prime is 77531045749. The next prime is 77531045873. The reversal of 77531045821 is 12854013577.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 77531045821 - 2⁷ = 77531045693 is a prime.

It is a super-2 number, since 2×77531045821² (a number of 23 digits) contains 22 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 (77531345821) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 482646 + ... + 622903.

It is an arithmetic number, because the mean of its divisors is an integer number (10204226500).

Almost surely, 2^77531045821 is an apocalyptic number.

It is an amenable number.

77531045821 is a deficient number, since it is larger than the sum of its proper divisors (4102766179).

77531045821 is a wasteful number, since it uses less digits than its factorization.

77531045821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1109259.

The product of its (nonzero) digits is 235200, while the sum is 43.

The spelling of 77531045821 in words is "seventy-seven billion, five hundred thirty-one million, forty-five thousand, eight hundred twenty-one".