61456538520 has 192 divisors, whose sum is σ = 215878965120. Its totient is φ = 15072832512.

The previous prime is 61456538519. The next prime is 61456538527. The reversal of 61456538520 is 2583565416.

61456538520 is a `hidden beast` number, since 6 + 1 + 4 + 565 + 3 + 85 + 2 + 0 = 666.

61456538520 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×61456538520² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61456538527) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1272657 + ... + 1320063.

It is an arithmetic number, because the mean of its divisors is an integer number (1124369610).

Almost surely, 2^61456538520 is an apocalyptic number.

61456538520 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 61456538520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (107939482560).

61456538520 is an abundant number, since it is smaller than the sum of its proper divisors (154422426600).

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

61456538520 is a wasteful number, since it uses less digits than its factorization.

61456538520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 47714 (or 47707 counting only the distinct ones).

The product of its (nonzero) digits is 864000, while the sum is 45.

The spelling of 61456538520 in words is "sixty-one billion, four hundred fifty-six million, five hundred thirty-eight thousand, five hundred twenty".