61643808 has 48 divisors (see below), whose sum is σ = 179796960. Its totient is φ = 20547648.

The previous prime is 61643797. The next prime is 61643831. The reversal of 61643808 is 80834616.

It is a happy number.

61643808 is a `hidden beast` number, since 6 + 1 + 643 + 8 + 0 + 8 = 666.

It is a tau number, because it is divible by the number of its divisors (48).

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

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 34810 + ... + 36537.

It is an arithmetic number, because the mean of its divisors is an integer number (3745770).

Almost surely, 2^61643808 is an apocalyptic number.

It is an amenable number.

61643808 is an abundant number, since it is smaller than the sum of its proper divisors (118153152).

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

61643808 is a wasteful number, since it uses less digits than its factorization.

61643808 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 71366 (or 71352 counting only the distinct ones).

The product of its (nonzero) digits is 27648, while the sum is 36.

The square root of 61643808 is about 7851.3570801486. The cubic root of 61643808 is about 395.0297643543.

The spelling of 61643808 in words is "sixty-one million, six hundred forty-three thousand, eight hundred eight".