61321515420 has 192 divisors, whose sum is σ = 197367528960. Its totient is φ = 14069145600.

The previous prime is 61321515383. The next prime is 61321515427. The reversal of 61321515420 is 2451512316.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61321515427) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 17065144 + ... + 17068736.

It is an arithmetic number, because the mean of its divisors is an integer number (1027955880).

Almost surely, 2^61321515420 is an apocalyptic number.

61321515420 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 61321515420, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (98683764480).

61321515420 is an abundant number, since it is smaller than the sum of its proper divisors (136046013540).

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

61321515420 is a wasteful number, since it uses less digits than its factorization.

61321515420 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4996 (or 4994 counting only the distinct ones).

The product of its (nonzero) digits is 7200, while the sum is 30.

The spelling of 61321515420 in words is "sixty-one billion, three hundred twenty-one million, five hundred fifteen thousand, four hundred twenty".