21397014 has 32 divisors (see below), whose sum is σ = 48023040. Its totient is φ = 7061256.

The previous prime is 21397009. The next prime is 21397043. The reversal of 21397014 is 41079312.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 3639 + ... + 7485.

It is an arithmetic number, because the mean of its divisors is an integer number (1500720).

Almost surely, 2^21397014 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21397014, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24011520).

21397014 is an abundant number, since it is smaller than the sum of its proper divisors (26626026).

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

21397014 is a wasteful number, since it uses less digits than its factorization.

21397014 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3961 (or 3955 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 21397014 is about 4625.6906511352. The cubic root of 21397014 is about 277.6201962872.

The spelling of 21397014 in words is "twenty-one million, three hundred ninety-seven thousand, fourteen".