20660655 has 8 divisors (see below), whose sum is σ = 33057072. Its totient is φ = 11019008.

The previous prime is 20660621. The next prime is 20660659. The reversal of 20660655 is 55606602.

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 20660655 - 2⁷ = 20660527 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20660659) 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, 688674 + ... + 688703.

It is an arithmetic number, because the mean of its divisors is an integer number (4132134).

Almost surely, 2^20660655 is an apocalyptic number.

20660655 is a deficient number, since it is larger than the sum of its proper divisors (12396417).

20660655 is a wasteful number, since it uses less digits than its factorization.

20660655 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1377385.

The product of its (nonzero) digits is 10800, while the sum is 30.

The square root of 20660655 is about 4545.3993223918. The cubic root of 20660655 is about 274.3982655572.

It can be divided in two parts, 20 and 660655, that added together give a triangular number (660675 = T₁₁₄₉).

The spelling of 20660655 in words is "twenty million, six hundred sixty thousand, six hundred fifty-five".