61021211020 has 192 divisors, whose sum is σ = 164163428352. Its totient is φ = 18498816000.

The previous prime is 61021210993. The next prime is 61021211023. The reversal of 61021211020 is 2011212016.

It is a junction number, because it is equal to n+sod(n) for n = 61021210985 and 61021211003.

It is not an unprimeable number, because it can be changed into a prime (61021211023) 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 63 ways as a sum of consecutive naturals, for example, 23549925 + ... + 23552515.

It is an arithmetic number, because the mean of its divisors is an integer number (855017856).

Almost surely, 2^61021211020 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61021211020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (82081714176).

61021211020 is an abundant number, since it is smaller than the sum of its proper divisors (103142217332).

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

61021211020 is a wasteful number, since it uses less digits than its factorization.

61021211020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3032 (or 3030 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 61021211020 its reverse (2011212016), we get a palindrome (63032423036).

The spelling of 61021211020 in words is "sixty-one billion, twenty-one million, two hundred eleven thousand, twenty".