61017600720 has 80 divisors (see below), whose sum is σ = 189333631872. Its totient is φ = 16255956480.

The previous prime is 61017600697. The next prime is 61017600817. The reversal of 61017600720 is 2700671016.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (80).

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

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 134829 + ... + 374451.

Almost surely, 2^61017600720 is an apocalyptic number.

61017600720 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

61017600720 is an abundant number, since it is smaller than the sum of its proper divisors (128316031152).

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

61017600720 is a wasteful number, since it uses less digits than its factorization.

61017600720 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 240700 (or 240694 counting only the distinct ones).

The product of its (nonzero) digits is 3528, while the sum is 30.

The spelling of 61017600720 in words is "sixty-one billion, seventeen million, six hundred thousand, seven hundred twenty".