21361478 has 4 divisors (see below), whose sum is σ = 32042220. Its totient is φ = 10680738.

The previous prime is 21361477. The next prime is 21361489. The reversal of 21361478 is 87416312.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21361477) 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 as a sum of consecutive naturals, namely, 5340368 + ... + 5340371.

It is an arithmetic number, because the mean of its divisors is an integer number (8010555).

Almost surely, 2^21361478 is an apocalyptic number.

21361478 is a deficient number, since it is larger than the sum of its proper divisors (10680742).

21361478 is a wasteful number, since it uses less digits than its factorization.

21361478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10680741.

The product of its digits is 8064, while the sum is 32.

The square root of 21361478 is about 4621.8478988387. The cubic root of 21361478 is about 277.4664212813.

The spelling of 21361478 in words is "twenty-one million, three hundred sixty-one thousand, four hundred seventy-eight".