21332378 has 4 divisors (see below), whose sum is σ = 31998570. Its totient is φ = 10666188.

The previous prime is 21332369. The next prime is 21332393. The reversal of 21332378 is 87323312.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 13786369 + 7546009 = 3713^2 + 2747^2 .

It is a super-2 number, since 2×21332378² = 910140702269768, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21332378.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5333093 + ... + 5333096.

Almost surely, 2^21332378 is an apocalyptic number.

21332378 is a deficient number, since it is larger than the sum of its proper divisors (10666192).

21332378 is a wasteful number, since it uses less digits than its factorization.

21332378 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10666191.

The product of its digits is 6048, while the sum is 29.

The square root of 21332378 is about 4618.6987344922. The cubic root of 21332378 is about 277.3403697338.

The spelling of 21332378 in words is "twenty-one million, three hundred thirty-two thousand, three hundred seventy-eight".