64444642 has 4 divisors (see below), whose sum is σ = 96666966. Its totient is φ = 32222320.

The previous prime is 64444621. The next prime is 64444649. The reversal of 64444642 is 24644446.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24644446 = 2 ⋅12322223.

It can be written as a sum of positive squares in only one way, i.e., 46117681 + 18326961 = 6791^2 + 4281^2 .

It is a super-2 number, since 2×64444642² = 8306223765016328, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 64444598 and 64444607.

It is not an unprimeable number, because it can be changed into a prime (64444649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16111159 + ... + 16111162.

Almost surely, 2^64444642 is an apocalyptic number.

64444642 is a deficient number, since it is larger than the sum of its proper divisors (32222324).

64444642 is a wasteful number, since it uses less digits than its factorization.

64444642 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32222323.

The product of its digits is 73728, while the sum is 34.

The square root of 64444642 is about 8027.7420237574. The cubic root of 64444642 is about 400.9242004891.

The spelling of 64444642 in words is "sixty-four million, four hundred forty-four thousand, six hundred forty-two".