66161440 has 48 divisors (see below), whose sum is σ = 161360640. Its totient is φ = 25608960.

The previous prime is 66161423. The next prime is 66161453. The reversal of 66161440 is 4416166.

It is a super-2 number, since 2×66161440² = 8754672285747200, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 66161399 and 66161408.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1710 + ... + 11629.

It is an arithmetic number, because the mean of its divisors is an integer number (3361680).

Almost surely, 2^66161440 is an apocalyptic number.

It is an amenable number.

66161440 is an abundant number, since it is smaller than the sum of its proper divisors (95199200).

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

66161440 is a wasteful number, since it uses less digits than its factorization.

66161440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13385 (or 13377 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 28.

The square root of 66161440 is about 8133.9682812266. The cubic root of 66161440 is about 404.4532376983.

The spelling of 66161440 in words is "sixty-six million, one hundred sixty-one thousand, four hundred forty".