21310942 has 4 divisors (see below), whose sum is σ = 31966416. Its totient is φ = 10655470.

The previous prime is 21310937. The next prime is 21310957. The reversal of 21310942 is 24901312.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5327734 + ... + 5327737.

It is an arithmetic number, because the mean of its divisors is an integer number (7991604).

Almost surely, 2^21310942 is an apocalyptic number.

21310942 is a deficient number, since it is larger than the sum of its proper divisors (10655474).

21310942 is a wasteful number, since it uses less digits than its factorization.

21310942 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10655473.

The product of its (nonzero) digits is 432, while the sum is 22.

The square root of 21310942 is about 4616.3775842104. The cubic root of 21310942 is about 277.2474427507.

The spelling of 21310942 in words is "twenty-one million, three hundred ten thousand, nine hundred forty-two".