20907747 has 16 divisors (see below), whose sum is σ = 35399680. Its totient is φ = 11947176.

The previous prime is 20907743. The next prime is 20907751. The reversal of 20907747 is 74770902.

It is an interprime number because it is at equal distance from previous prime (20907743) and next prime (20907751).

It is not a de Polignac number, because 20907747 - 2² = 20907743 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20907743) 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, 55123 + ... + 55500.

It is an arithmetic number, because the mean of its divisors is an integer number (2212480).

Almost surely, 2^20907747 is an apocalyptic number.

20907747 is a gapful number since it is divisible by the number (27) formed by its first and last digit.

20907747 is a deficient number, since it is larger than the sum of its proper divisors (14491933).

20907747 is a wasteful number, since it uses less digits than its factorization.

20907747 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110639 (or 110633 counting only the distinct ones).

The product of its (nonzero) digits is 24696, while the sum is 36.

The square root of 20907747 is about 4572.4989885182. The cubic root of 20907747 is about 275.4878261381.

The spelling of 20907747 in words is "twenty million, nine hundred seven thousand, seven hundred forty-seven".