64143661 has 4 divisors (see below), whose sum is σ = 64229824. Its totient is φ = 64057500.

The previous prime is 64143649. The next prime is 64143683. The reversal of 64143661 is 16634146.

64143661 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 64143661 - 2¹⁹ = 63619373 is a prime.

It is a super-2 number, since 2×64143661² = 8228818492965842, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (64143631) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41955 + ... + 43456.

It is an arithmetic number, because the mean of its divisors is an integer number (16057456).

Almost surely, 2^64143661 is an apocalyptic number.

It is an amenable number.

64143661 is a deficient number, since it is larger than the sum of its proper divisors (86163).

64143661 is an equidigital number, since it uses as much as digits as its factorization.

64143661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 86162.

The product of its digits is 10368, while the sum is 31.

The square root of 64143661 is about 8008.9737794551. The cubic root of 64143661 is about 400.2990700870.

The spelling of 64143661 in words is "sixty-four million, one hundred forty-three thousand, six hundred sixty-one".