20629749 has 16 divisors (see below), whose sum is σ = 31680000. Its totient is φ = 11696880.

The previous prime is 20629747. The next prime is 20629751. The reversal of 20629749 is 94792602.

It is an interprime number because it is at equal distance from previous prime (20629747) and next prime (20629751).

It is not a de Polignac number, because 20629749 - 2¹ = 20629747 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20629747) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 999 + ... + 6500.

It is an arithmetic number, because the mean of its divisors is an integer number (1980000).

Almost surely, 2^20629749 is an apocalyptic number.

It is an amenable number.

20629749 is a deficient number, since it is larger than the sum of its proper divisors (11050251).

20629749 is a wasteful number, since it uses less digits than its factorization.

20629749 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7640.

The product of its (nonzero) digits is 54432, while the sum is 39.

The square root of 20629749 is about 4541.9983487447. The cubic root of 20629749 is about 274.2613743670.

It can be divided in two parts, 2062 and 9749, that added together give a palindrome (11811).

The spelling of 20629749 in words is "twenty million, six hundred twenty-nine thousand, seven hundred forty-nine".