21859875386 has 4 divisors (see below), whose sum is σ = 32789813082. Its totient is φ = 10929937692.

The previous prime is 21859875371. The next prime is 21859875409. The reversal of 21859875386 is 68357895812.

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., 21776609761 + 83265625 = 147569^2 + 9125^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5464968845 + ... + 5464968848.

Almost surely, 2^21859875386 is an apocalyptic number.

21859875386 is a deficient number, since it is larger than the sum of its proper divisors (10929937696).

21859875386 is a wasteful number, since it uses less digits than its factorization.

21859875386 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10929937695.

The product of its digits is 29030400, while the sum is 62.

The spelling of 21859875386 in words is "twenty-one billion, eight hundred fifty-nine million, eight hundred seventy-five thousand, three hundred eighty-six".