21747064 has 8 divisors (see below), whose sum is σ = 40775760. Its totient is φ = 10873528.

The previous prime is 21747059. The next prime is 21747073. The reversal of 21747064 is 46074712.

It is a tau number, because it is divible by the number of its divisors (8).

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, 1359184 + ... + 1359199.

It is an arithmetic number, because the mean of its divisors is an integer number (5096970).

Almost surely, 2^21747064 is an apocalyptic number.

It is an amenable number.

21747064 is a deficient number, since it is larger than the sum of its proper divisors (19028696).

21747064 is a wasteful number, since it uses less digits than its factorization.

21747064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2718389 (or 2718385 counting only the distinct ones).

The product of its (nonzero) digits is 9408, while the sum is 31.

The square root of 21747064 is about 4663.3747436808. The cubic root of 21747064 is about 279.1259478543.

The spelling of 21747064 in words is "twenty-one million, seven hundred forty-seven thousand, sixty-four".