65661844 has 12 divisors (see below), whose sum is σ = 118615168. Its totient is φ = 31771800.

The previous prime is 65661833. The next prime is 65661863. The reversal of 65661844 is 44816656.

It is a happy number.

It is a super-2 number, since 2×65661844² = 8622955514960672, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 65661797 and 65661806.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 264642 + ... + 264889.

Almost surely, 2^65661844 is an apocalyptic number.

It is an amenable number.

65661844 is a deficient number, since it is larger than the sum of its proper divisors (52953324).

65661844 is a wasteful number, since it uses less digits than its factorization.

65661844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 529566 (or 529564 counting only the distinct ones).

The product of its digits is 138240, while the sum is 40.

The square root of 65661844 is about 8103.1996149669. The cubic root of 65661844 is about 403.4326333076.

It can be divided in two parts, 656 and 61844, that added together give a square (62500 = 250²).

The spelling of 65661844 in words is "sixty-five million, six hundred sixty-one thousand, eight hundred forty-four".