20649429 has 12 divisors (see below), whose sum is σ = 29889132. Its totient is φ = 13737600.

The previous prime is 20649413. The next prime is 20649439. The reversal of 20649429 is 92494602.

20649429 is a `hidden beast` number, since 2 + 0 + 649 + 4 + 2 + 9 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 15800625 + 4848804 = 3975^2 + 2202^2 .

It is not a de Polignac number, because 20649429 - 2⁴ = 20649413 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20649393 and 20649402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20649439) 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, 2749 + ... + 6989.

It is an arithmetic number, because the mean of its divisors is an integer number (2490761).

Almost surely, 2^20649429 is an apocalyptic number.

It is an amenable number.

20649429 is a deficient number, since it is larger than the sum of its proper divisors (9239703).

20649429 is a wasteful number, since it uses less digits than its factorization.

20649429 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4788 (or 4785 counting only the distinct ones).

The product of its (nonzero) digits is 31104, while the sum is 36.

The square root of 20649429 is about 4544.1642796008. The cubic root of 20649429 is about 274.3485583076.

The spelling of 20649429 in words is "twenty million, six hundred forty-nine thousand, four hundred twenty-nine".