21400067 has 8 divisors (see below), whose sum is σ = 23437680. Its totient is φ = 19418400.

The previous prime is 21400063. The next prime is 21400069. The reversal of 21400067 is 76000412.

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

It is a cyclic number.

It is not a de Polignac number, because 21400067 - 2² = 21400063 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21400063) 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, 13184 + ... + 14717.

It is an arithmetic number, because the mean of its divisors is an integer number (2929710).

Almost surely, 2^21400067 is an apocalyptic number.

21400067 is a deficient number, since it is larger than the sum of its proper divisors (2037613).

21400067 is a wasteful number, since it uses less digits than its factorization.

21400067 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27973.

The product of its (nonzero) digits is 336, while the sum is 20.

The square root of 21400067 is about 4626.0206441390. The cubic root of 21400067 is about 277.6333995960.

Adding to 21400067 its reverse (76000412), we get a palindrome (97400479).

The spelling of 21400067 in words is "twenty-one million, four hundred thousand, sixty-seven".