61810840 has 64 divisors (see below), whose sum is σ = 171178560. Its totient is φ = 19560960.

The previous prime is 61810829. The next prime is 61810843. The reversal of 61810840 is 4801816.

61810840 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a junction number, because it is equal to n+sod(n) for n = 61810799 and 61810808.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61810843) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4851 + ... + 12130.

It is an arithmetic number, because the mean of its divisors is an integer number (2674665).

Almost surely, 2^61810840 is an apocalyptic number.

It is an amenable number.

61810840 is an abundant number, since it is smaller than the sum of its proper divisors (109367720).

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

61810840 is a wasteful number, since it uses less digits than its factorization.

61810840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 17012 (or 17008 counting only the distinct ones).

The product of its (nonzero) digits is 1536, while the sum is 28.

The square root of 61810840 is about 7861.9870261913. The cubic root of 61810840 is about 395.3862376002.

It can be divided in two parts, 61 and 810840, that added together give a triangular number (810901 = T₁₂₇₃).

The spelling of 61810840 in words is "sixty-one million, eight hundred ten thousand, eight hundred forty".