21477867 has 8 divisors (see below), whose sum is σ = 28687824. Its totient is φ = 14293248.

The previous prime is 21477853. The next prime is 21477877. The reversal of 21477867 is 76877412.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21477867 - 2⁶ = 21477803 is a prime.

It is a super-2 number, since 2×21477867² = 922597541739378, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21477877) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4258 + ... + 7815.

It is an arithmetic number, because the mean of its divisors is an integer number (3585978).

Almost surely, 2^21477867 is an apocalyptic number.

21477867 is a deficient number, since it is larger than the sum of its proper divisors (7209957).

21477867 is a wasteful number, since it uses less digits than its factorization.

21477867 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12669.

The product of its digits is 131712, while the sum is 42.

The square root of 21477867 is about 4634.4219704295. The cubic root of 21477867 is about 277.9694383532.

The spelling of 21477867 in words is "twenty-one million, four hundred seventy-seven thousand, eight hundred sixty-seven".