21747134 has 16 divisors (see below), whose sum is σ = 34558080. Its totient is φ = 10235160.

The previous prime is 21747133. The next prime is 21747149. The reversal of 21747134 is 43174712.

It is a junction number, because it is equal to n+sod(n) for n = 21747097 and 21747106.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21747133) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4439 + ... + 7949.

It is an arithmetic number, because the mean of its divisors is an integer number (2159880).

Almost surely, 2^21747134 is an apocalyptic number.

21747134 is a deficient number, since it is larger than the sum of its proper divisors (12810946).

21747134 is a wasteful number, since it uses less digits than its factorization.

21747134 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3695.

The product of its digits is 4704, while the sum is 29.

The square root of 21747134 is about 4663.3822489691. The cubic root of 21747134 is about 279.1262473399.

The spelling of 21747134 in words is "twenty-one million, seven hundred forty-seven thousand, one hundred thirty-four".