21067589954 has 4 divisors (see below), whose sum is σ = 31601384934. Its totient is φ = 10533794976.

The previous prime is 21067589927. The next prime is 21067589969. The reversal of 21067589954 is 45998576012.

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., 13127888929 + 7939701025 = 114577^2 + 89105^2 .

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 21067589954.

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, 5266897487 + ... + 5266897490.

Almost surely, 2^21067589954 is an apocalyptic number.

21067589954 is a deficient number, since it is larger than the sum of its proper divisors (10533794980).

21067589954 is a wasteful number, since it uses less digits than its factorization.

21067589954 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10533794979.

The product of its (nonzero) digits is 5443200, while the sum is 56.

The spelling of 21067589954 in words is "twenty-one billion, sixty-seven million, five hundred eighty-nine thousand, nine hundred fifty-four".