61474076821 has 2 divisors, whose sum is σ = 61474076822. Its totient is φ = 61474076820.

The previous prime is 61474076819. The next prime is 61474076849. The reversal of 61474076821 is 12867047416.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 61459863921 + 14212900 = 247911^2 + 3770^2 .

It is a cyclic number.

It is not a de Polignac number, because 61474076821 - 2¹ = 61474076819 is a prime.

Together with 61474076819, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61474076801) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30737038410 + 30737038411.

It is an arithmetic number, because the mean of its divisors is an integer number (30737038411).

Almost surely, 2^61474076821 is an apocalyptic number.

It is an amenable number.

61474076821 is a deficient number, since it is larger than the sum of its proper divisors (1).

61474076821 is an equidigital number, since it uses as much as digits as its factorization.

61474076821 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 451584, while the sum is 46.

The spelling of 61474076821 in words is "sixty-one billion, four hundred seventy-four million, seventy-six thousand, eight hundred twenty-one".