61307640 has 48 divisors (see below), whose sum is σ = 199251000. Its totient is φ = 16348608.

The previous prime is 61307621. The next prime is 61307641. The reversal of 61307640 is 4670316.

61307640 is a `hidden beast` number, since 6 + 13 + 0 + 7 + 640 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61307641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 84790 + ... + 85509.

Almost surely, 2^61307640 is an apocalyptic number.

61307640 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

61307640 is an abundant number, since it is smaller than the sum of its proper divisors (137943360).

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

61307640 is a wasteful number, since it uses less digits than its factorization.

61307640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170316 (or 170309 counting only the distinct ones).

The product of its (nonzero) digits is 3024, while the sum is 27.

The square root of 61307640 is about 7829.9195398165. The cubic root of 61307640 is about 394.3103706788.

Adding to 61307640 its reverse (4670316), we get a palindrome (65977956).

The spelling of 61307640 in words is "sixty-one million, three hundred seven thousand, six hundred forty".