61583640 has 64 divisors (see below), whose sum is σ = 189272160. Its totient is φ = 16020480.

The previous prime is 61583633. The next prime is 61583659. The reversal of 61583640 is 4638516.

61583640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

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, 1339 + ... + 11178.

Almost surely, 2^61583640 is an apocalyptic number.

61583640 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 61583640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (94636080).

61583640 is an abundant number, since it is smaller than the sum of its proper divisors (127688520).

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

61583640 is a wasteful number, since it uses less digits than its factorization.

61583640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12572 (or 12568 counting only the distinct ones).

The product of its (nonzero) digits is 17280, while the sum is 33.

The square root of 61583640 is about 7847.5244504238. The cubic root of 61583640 is about 394.9011983833.

It can be divided in two parts, 615 and 83640, that added together give a triangular number (84255 = T₄₁₀).

The spelling of 61583640 in words is "sixty-one million, five hundred eighty-three thousand, six hundred forty".