21042376 has 32 divisors (see below), whose sum is σ = 40320000. Its totient is φ = 10293696.

The previous prime is 21042353. The next prime is 21042383. The reversal of 21042376 is 67324012.

It is a self number, because there is not a number n which added to its sum of digits gives 21042376.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 141150 + ... + 141298.

It is an arithmetic number, because the mean of its divisors is an integer number (1260000).

Almost surely, 2^21042376 is an apocalyptic number.

It is an amenable number.

21042376 is a deficient number, since it is larger than the sum of its proper divisors (19277624).

21042376 is a wasteful number, since it uses less digits than its factorization.

21042376 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 421 (or 417 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 25.

The square root of 21042376 is about 4587.1969654681. The cubic root of 21042376 is about 276.0778678282.

Adding to 21042376 its reverse (67324012), we get a palindrome (88366388).

The spelling of 21042376 in words is "twenty-one million, forty-two thousand, three hundred seventy-six".