61957509120 has 1040 divisors, whose sum is σ = 254755171440. Its totient is φ = 14353956864.

The previous prime is 61957509109. The next prime is 61957509121. The reversal of 61957509120 is 2190575916.

61957509120 is a `hidden beast` number, since 6 + 19 + 5 + 7 + 509 + 120 = 666.

It can be written as a sum of positive squares in 8 ways, for example, as 38128029696 + 23829479424 = 195264^2 + 154368^2 .

It is a tau number, because it is divible by the number of its divisors (1040).

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

It is a Saint-Exupery number, since it is equal to the product of the sides of a Pythagorean triangle: 5304 × 4680 × 2496.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61957509121) by changing a digit.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 3644559352 + ... + 3644559368.

Almost surely, 2^61957509120 is an apocalyptic number.

61957509120 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 61957509120, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (127377585720).

61957509120 is an abundant number, since it is smaller than the sum of its proper divisors (192797662320).

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

61957509120 is an equidigital number, since it uses as much as digits as its factorization.

61957509120 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 97 (or 40 counting only the distinct ones).

The product of its (nonzero) digits is 170100, while the sum is 45.

The spelling of 61957509120 in words is "sixty-one billion, nine hundred fifty-seven million, five hundred nine thousand, one hundred twenty".