64661606 has 4 divisors (see below), whose sum is σ = 96992412. Its totient is φ = 32330802.

The previous prime is 64661603. The next prime is 64661621. The reversal of 64661606 is 60616646.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 60616646 = 2 ⋅30308323.

It is a super-2 number, since 2×64661606² = 8362246580998472, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64661603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16165400 + ... + 16165403.

It is an arithmetic number, because the mean of its divisors is an integer number (24248103).

Almost surely, 2^64661606 is an apocalyptic number.

64661606 is a deficient number, since it is larger than the sum of its proper divisors (32330806).

64661606 is a wasteful number, since it uses less digits than its factorization.

64661606 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32330805.

The product of its (nonzero) digits is 31104, while the sum is 35.

The square root of 64661606 is about 8041.2440579801. The cubic root of 64661606 is about 401.3736233311.

The spelling of 64661606 in words is "sixty-four million, six hundred sixty-one thousand, six hundred six".