61517526840 has 1280 divisors, whose sum is σ = 274591088640. Its totient is φ = 11975040000.

The previous prime is 61517526821. The next prime is 61517526853. The reversal of 61517526840 is 4862571516.

61517526840 is a `hidden beast` number, since 6 + 1 + 517 + 52 + 6 + 84 + 0 = 666.

It is a super-2 number, since 2×61517526840² (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 an unprimeable number.

It is a polite number, since it can be written in 319 ways as a sum of consecutive naturals, for example, 407400765 + ... + 407400915.

It is an arithmetic number, because the mean of its divisors is an integer number (214524288).

Almost surely, 2^61517526840 is an apocalyptic number.

61517526840 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 61517526840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (137295544320).

61517526840 is an abundant number, since it is smaller than the sum of its proper divisors (213073561800).

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

61517526840 is a wasteful number, since it uses less digits than its factorization.

61517526840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 286 (or 273 counting only the distinct ones).

The product of its (nonzero) digits is 403200, while the sum is 45.

The spelling of 61517526840 in words is "sixty-one billion, five hundred seventeen million, five hundred twenty-six thousand, eight hundred forty".