21267078 has 24 divisors (see below), whose sum is σ = 49479192. Its totient is φ = 6076224.

The previous prime is 21267067. The next prime is 21267079. The reversal of 21267078 is 87076212.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21267079) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 35875 + ... + 36462.

It is an arithmetic number, because the mean of its divisors is an integer number (2061633).

Almost surely, 2^21267078 is an apocalyptic number.

21267078 is an abundant number, since it is smaller than the sum of its proper divisors (28212114).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21267078 is a wasteful number, since it uses less digits than its factorization.

21267078 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 72356 (or 72349 counting only the distinct ones).

The product of its (nonzero) digits is 9408, while the sum is 33.

The square root of 21267078 is about 4611.6242258016. The cubic root of 21267078 is about 277.0570939757.

The spelling of 21267078 in words is "twenty-one million, two hundred sixty-seven thousand, seventy-eight".