61213366520 has 32 divisors (see below), whose sum is σ = 139389480720. Its totient is φ = 24190341120.

The previous prime is 61213366481. The next prime is 61213366523. The reversal of 61213366520 is 2566331216.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61213366523) 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 in 7 ways as a sum of consecutive naturals, for example, 9215561 + ... + 9222200.

Almost surely, 2^61213366520 is an apocalyptic number.

It is an amenable number.

61213366520 is an abundant number, since it is smaller than the sum of its proper divisors (78176114200).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

61213366520 is a wasteful number, since it uses less digits than its factorization.

61213366520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18437855 (or 18437851 counting only the distinct ones).

The product of its (nonzero) digits is 38880, while the sum is 35.

Adding to 61213366520 its reverse (2566331216), we get a palindrome (63779697736).

The spelling of 61213366520 in words is "sixty-one billion, two hundred thirteen million, three hundred sixty-six thousand, five hundred twenty".