61842251521 has 4 divisors (see below), whose sum is σ = 61945151044. Its totient is φ = 61739352000.

The previous prime is 61842251507. The next prime is 61842251543. The reversal of 61842251521 is 12515224816.

61842251521 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 42492050496 + 19350201025 = 206136^2 + 139105^2 .

It is a cyclic number.

It is not a de Polignac number, because 61842251521 - 2¹¹ = 61842249473 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (61842251561) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 51448860 + ... + 51450061.

It is an arithmetic number, because the mean of its divisors is an integer number (15486287761).

Almost surely, 2^61842251521 is an apocalyptic number.

It is an amenable number.

61842251521 is a deficient number, since it is larger than the sum of its proper divisors (102899523).

61842251521 is a wasteful number, since it uses less digits than its factorization.

61842251521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 102899522.

The product of its digits is 38400, while the sum is 37.

The spelling of 61842251521 in words is "sixty-one billion, eight hundred forty-two million, two hundred fifty-one thousand, five hundred twenty-one".