21743902 has 4 divisors (see below), whose sum is σ = 32615856. Its totient is φ = 10871950.

The previous prime is 21743893. The next prime is 21743903. The reversal of 21743902 is 20934712.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21743903) by changing a digit.

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 as a sum of consecutive naturals, namely, 5435974 + ... + 5435977.

It is an arithmetic number, because the mean of its divisors is an integer number (8153964).

Almost surely, 2^21743902 is an apocalyptic number.

21743902 is a deficient number, since it is larger than the sum of its proper divisors (10871954).

21743902 is a wasteful number, since it uses less digits than its factorization.

21743902 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10871953.

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 21743902 is about 4663.0357064899. The cubic root of 21743902 is about 279.1124189932.

The spelling of 21743902 in words is "twenty-one million, seven hundred forty-three thousand, nine hundred two".