61328393977821 has 32 divisors (see below), whose sum is σ = 86391235708800. Its totient is φ = 38698781401728.

The previous prime is 61328393977787. The next prime is 61328393977843. The reversal of 61328393977821 is 12877939382316.

It is not a de Polignac number, because 61328393977821 - 2¹⁰ = 61328393976797 is a prime.

It is a super-2 number, since 2×61328393977821² (a number of 28 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61328393970821) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 21476145 + ... + 24163641.

It is an arithmetic number, because the mean of its divisors is an integer number (2699726115900).

Almost surely, 2^{61328393977821} is an apocalyptic number.

It is an amenable number.

61328393977821 is a deficient number, since it is larger than the sum of its proper divisors (25062841730979).

61328393977821 is a wasteful number, since it uses less digits than its factorization.

61328393977821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2688666 (or 2688628 counting only the distinct ones).

The product of its digits is 164602368, while the sum is 69.

The spelling of 61328393977821 in words is "sixty-one trillion, three hundred twenty-eight billion, three hundred ninety-three million, nine hundred seventy-seven thousand, eight hundred twenty-one".