21960709 has 8 divisors (see below), whose sum is σ = 22552992. Its totient is φ = 21375120.

The previous prime is 21960683. The next prime is 21960727. The reversal of 21960709 is 90706912.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21960709 - 2⁵ = 21960677 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21960769) 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, 5362 + ... + 8524.

It is an arithmetic number, because the mean of its divisors is an integer number (2819124).

Almost surely, 2^21960709 is an apocalyptic number.

It is an amenable number.

21960709 is a deficient number, since it is larger than the sum of its proper divisors (592283).

21960709 is a wasteful number, since it uses less digits than its factorization.

21960709 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3347.

The product of its (nonzero) digits is 6804, while the sum is 34.

The square root of 21960709 is about 4686.2254533900. The cubic root of 21960709 is about 280.0370231656.

The spelling of 21960709 in words is "twenty-one million, nine hundred sixty thousand, seven hundred nine".