21397146 has 8 divisors (see below), whose sum is σ = 42794304. Its totient is φ = 7132380.

The previous prime is 21397139. The next prime is 21397171. The reversal of 21397146 is 64179312.

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

21397146 is an admirable number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1783090 + ... + 1783101.

It is an arithmetic number, because the mean of its divisors is an integer number (5349288).

Almost surely, 2^21397146 is an apocalyptic number.

21397146 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

21397146 is a wasteful number, since it uses less digits than its factorization.

21397146 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3566196.

The product of its digits is 9072, while the sum is 33.

The square root of 21397146 is about 4625.7049192528. The cubic root of 21397146 is about 277.6207671735.

The spelling of 21397146 in words is "twenty-one million, three hundred ninety-seven thousand, one hundred forty-six".