61533520653221 has 16 divisors (see below), whose sum is σ = 61786144243200. Its totient is φ = 61281539465328.

The previous prime is 61533520653203. The next prime is 61533520653233. The reversal of 61533520653221 is 12235602533516.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 61533520653221 - 2³⁸ = 61258642746277 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 (61533520650221) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 522390110 + ... + 522507888.

It is an arithmetic number, because the mean of its divisors is an integer number (3861634015200).

Almost surely, 2^{61533520653221} is an apocalyptic number.

It is an amenable number.

61533520653221 is a deficient number, since it is larger than the sum of its proper divisors (252623589979).

61533520653221 is a wasteful number, since it uses less digits than its factorization.

61533520653221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120488.

The product of its (nonzero) digits is 972000, while the sum is 44.

The spelling of 61533520653221 in words is "sixty-one trillion, five hundred thirty-three billion, five hundred twenty million, six hundred fifty-three thousand, two hundred twenty-one".