61647040 has 224 divisors, whose sum is σ = 189463680. Its totient is φ = 18579456.

The previous prime is 61647017. The next prime is 61647041. The reversal of 61647040 is 4074616.

It is a tau number, because it is divible by the number of its divisors (224).

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

It is not an unprimeable number, because it can be changed into a prime (61647041) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 844444 + ... + 844516.

It is an arithmetic number, because the mean of its divisors is an integer number (845820).

Almost surely, 2^61647040 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 61647040, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94731840).

61647040 is an abundant number, since it is smaller than the sum of its proper divisors (127816640).

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

61647040 is a wasteful number, since it uses less digits than its factorization.

61647040 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 139 (or 129 counting only the distinct ones).

The product of its (nonzero) digits is 4032, while the sum is 28.

The square root of 61647040 is about 7851.5629017413. The cubic root of 61647040 is about 395.0366680696.

The spelling of 61647040 in words is "sixty-one million, six hundred forty-seven thousand, forty".