61705726992 has 320 divisors, whose sum is σ = 220164241920. Its totient is φ = 16111872000.

The previous prime is 61705726949. The next prime is 61705727047. The reversal of 61705726992 is 29962750716.

61705726992 is a `hidden beast` number, since 6 + 1 + 7 + 0 + 572 + 69 + 9 + 2 = 666.

61705726992 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 2×61705726992² (a number of 22 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 3962742 + ... + 3978282.

It is an arithmetic number, because the mean of its divisors is an integer number (688013256).

Almost surely, 2^61705726992 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 61705726992, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (110082120960).

61705726992 is an abundant number, since it is smaller than the sum of its proper divisors (158458514928).

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

61705726992 is a wasteful number, since it uses less digits than its factorization.

61705726992 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15679 (or 15667 counting only the distinct ones).

The product of its (nonzero) digits is 2857680, while the sum is 54.

The spelling of 61705726992 in words is "sixty-one billion, seven hundred five million, seven hundred twenty-six thousand, nine hundred ninety-two".