61668281 has 8 divisors (see below), whose sum is σ = 65490720. Its totient is φ = 57903552.

The previous prime is 61668251. The next prime is 61668287. The reversal of 61668281 is 18286616.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-61668281 is a prime.

It is a super-2 number, since 2×61668281² = 7605953762989922, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (61668287) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 12215 + ... + 16508.

It is an arithmetic number, because the mean of its divisors is an integer number (8186340).

Almost surely, 2^61668281 is an apocalyptic number.

It is an amenable number.

61668281 is a deficient number, since it is larger than the sum of its proper divisors (3822439).

61668281 is a wasteful number, since it uses less digits than its factorization.

61668281 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28855.

The product of its digits is 27648, while the sum is 38.

The square root of 61668281 is about 7852.9154458710. The cubic root of 61668281 is about 395.0820339153.

The spelling of 61668281 in words is "sixty-one million, six hundred sixty-eight thousand, two hundred eighty-one".