20666701 has 4 divisors (see below), whose sum is σ = 22545504. Its totient is φ = 18787900.

The previous prime is 20666689. The next prime is 20666743. The reversal of 20666701 is 10766602.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 20666701 - 2⁵ = 20666669 is a prime.

It is a super-2 number, since 2×20666701² = 854225060446802, which contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 20666701.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20666791) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 939385 + ... + 939406.

It is an arithmetic number, because the mean of its divisors is an integer number (5636376).

Almost surely, 2^20666701 is an apocalyptic number.

It is an amenable number.

20666701 is a deficient number, since it is larger than the sum of its proper divisors (1878803).

20666701 is a wasteful number, since it uses less digits than its factorization.

20666701 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1878802.

The product of its (nonzero) digits is 3024, while the sum is 28.

The square root of 20666701 is about 4546.0643418236. The cubic root of 20666701 is about 274.4250289893.

Subtracting from 20666701 its reverse (10766602), we obtain a palindrome (9900099).

The spelling of 20666701 in words is "twenty million, six hundred sixty-six thousand, seven hundred one".