20969767 has 32 divisors (see below), whose sum is σ = 27675648. Its totient is φ = 15434496.

The previous prime is 20969723. The next prime is 20969783. The reversal of 20969767 is 76796902.

It is a de Polignac number, because none of the positive numbers 2^k-20969767 is a prime.

It is a super-2 number, since 2×20969767² = 879462256068578, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20960767) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 89883 + ... + 90115.

It is an arithmetic number, because the mean of its divisors is an integer number (864864).

Almost surely, 2^20969767 is an apocalyptic number.

20969767 is a deficient number, since it is larger than the sum of its proper divisors (6705881).

20969767 is a wasteful number, since it uses less digits than its factorization.

20969767 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 319.

The product of its (nonzero) digits is 285768, while the sum is 46.

The square root of 20969767 is about 4579.2758161089. The cubic root of 20969767 is about 275.7599563453.

It can be divided in two parts, 209697 and 67, that added together give a square (209764 = 458²).

The spelling of 20969767 in words is "twenty million, nine hundred sixty-nine thousand, seven hundred sixty-seven".