20667789 has 12 divisors (see below), whose sum is σ = 29910972. Its totient is φ = 13752000.

The previous prime is 20667737. The next prime is 20667811. The reversal of 20667789 is 98776602.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 17994564 + 2673225 = 4242^2 + 1635^2 .

It is not a de Polignac number, because 20667789 - 2⁸ = 20667533 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20667709) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3499 + ... + 7319.

It is an arithmetic number, because the mean of its divisors is an integer number (2492581).

Almost surely, 2^20667789 is an apocalyptic number.

It is an amenable number.

20667789 is a deficient number, since it is larger than the sum of its proper divisors (9243183).

20667789 is a wasteful number, since it uses less digits than its factorization.

20667789 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4428 (or 4425 counting only the distinct ones).

The product of its (nonzero) digits is 254016, while the sum is 45.

The square root of 20667789 is about 4546.1840041952. The cubic root of 20667789 is about 274.4298446135.

The spelling of 20667789 in words is "twenty million, six hundred sixty-seven thousand, seven hundred eighty-nine".