61375028021 has 2 divisors, whose sum is σ = 61375028022. Its totient is φ = 61375028020.

The previous prime is 61375027991. The next prime is 61375028047. The reversal of 61375028021 is 12082057316.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 59969152996 + 1405875025 = 244886^2 + 37495^2 .

It is a cyclic number.

It is not a de Polignac number, because 61375028021 - 2³⁰ = 60301286197 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (61375028321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 30687514010 + 30687514011.

It is an arithmetic number, because the mean of its divisors is an integer number (30687514011).

Almost surely, 2^61375028021 is an apocalyptic number.

It is an amenable number.

61375028021 is a deficient number, since it is larger than the sum of its proper divisors (1).

61375028021 is an equidigital number, since it uses as much as digits as its factorization.

61375028021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 20160, while the sum is 35.

The spelling of 61375028021 in words is "sixty-one billion, three hundred seventy-five million, twenty-eight thousand, twenty-one".