20718461 has 8 divisors (see below), whose sum is σ = 22216320. Its totient is φ = 19251648.

The previous prime is 20718443. The next prime is 20718463. The reversal of 20718461 is 16481702.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20718461 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 (20718463) 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, 6371 + ... + 9056.

It is an arithmetic number, because the mean of its divisors is an integer number (2777040).

Almost surely, 2^20718461 is an apocalyptic number.

It is an amenable number.

20718461 is a deficient number, since it is larger than the sum of its proper divisors (1497859).

20718461 is a wasteful number, since it uses less digits than its factorization.

20718461 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15523.

The product of its (nonzero) digits is 2688, while the sum is 29.

The square root of 20718461 is about 4551.7536181125. The cubic root of 20718461 is about 274.6539382501.

The spelling of 20718461 in words is "twenty million, seven hundred eighteen thousand, four hundred sixty-one".