64561331642 has 4 divisors (see below), whose sum is σ = 96841997466. Its totient is φ = 32280665820.

The previous prime is 64561331633. The next prime is 64561331657. The reversal of 64561331642 is 24613316546.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 42769962481 + 21791369161 = 206809^2 + 147619^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 64561331642.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16140332909 + ... + 16140332912.

Almost surely, 2^64561331642 is an apocalyptic number.

64561331642 is a deficient number, since it is larger than the sum of its proper divisors (32280665824).

64561331642 is a wasteful number, since it uses less digits than its factorization.

64561331642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32280665823.

The product of its digits is 311040, while the sum is 41.

The spelling of 64561331642 in words is "sixty-four billion, five hundred sixty-one million, three hundred thirty-one thousand, six hundred forty-two".