61421523221 has 8 divisors (see below), whose sum is σ = 61602991800. Its totient is φ = 61240294080.

The previous prime is 61421523143. The next prime is 61421523257. The reversal of 61421523221 is 12232512416.

It can be written as a sum of positive squares in 4 ways, for example, as 37322376100 + 24099147121 = 193190^2 + 155239^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61421523221 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 (61421523271) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 460595 + ... + 578783.

It is an arithmetic number, because the mean of its divisors is an integer number (7700373975).

Almost surely, 2^61421523221 is an apocalyptic number.

It is an amenable number.

61421523221 is a deficient number, since it is larger than the sum of its proper divisors (181468579).

61421523221 is a wasteful number, since it uses less digits than its factorization.

61421523221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 119719.

The product of its digits is 5760, while the sum is 29.

The spelling of 61421523221 in words is "sixty-one billion, four hundred twenty-one million, five hundred twenty-three thousand, two hundred twenty-one".