61645536 has 120 divisors (see below), whose sum is σ = 192099600. Its totient is φ = 19325952.

The previous prime is 61645471. The next prime is 61645627. The reversal of 61645536 is 63554616.

61645536 is a `hidden beast` number, since 6 + 1 + 645 + 5 + 3 + 6 = 666.

It is a super-3 number, since 3×61645536³ (a number of 24 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a self number, because there is not a number n which added to its sum of digits gives 61645536.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 43365 + ... + 44763.

It is an arithmetic number, because the mean of its divisors is an integer number (1600830).

Almost surely, 2^61645536 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 61645536, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (96049800).

61645536 is an abundant number, since it is smaller than the sum of its proper divisors (130454064).

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

61645536 is a wasteful number, since it uses less digits than its factorization.

61645536 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1438 (or 1421 counting only the distinct ones).

The product of its digits is 64800, while the sum is 36.

The square root of 61645536 is about 7851.4671240476. The cubic root of 61645536 is about 395.0334554796.

The spelling of 61645536 in words is "sixty-one million, six hundred forty-five thousand, five hundred thirty-six".