21014399 has 8 divisors (see below), whose sum is σ = 25280640. Its totient is φ = 17064216.

The previous prime is 21014381. The next prime is 21014407. The reversal of 21014399 is 99341012.

It is a happy number.

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 21014399 - 2²⁴ = 4237183 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21014339) 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, 78869 + ... + 79134.

It is an arithmetic number, because the mean of its divisors is an integer number (3160080).

Almost surely, 2^21014399 is an apocalyptic number.

21014399 is a deficient number, since it is larger than the sum of its proper divisors (4266241).

21014399 is a wasteful number, since it uses less digits than its factorization.

21014399 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 158029.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 21014399 is about 4584.1464854431. The cubic root of 21014399 is about 275.9554599764.

The spelling of 21014399 in words is "twenty-one million, fourteen thousand, three hundred ninety-nine".