20213740 has 12 divisors (see below), whose sum is σ = 42448896. Its totient is φ = 8085488.

The previous prime is 20213719. The next prime is 20213747. The reversal of 20213740 is 4731202.

It is not an unprimeable number, because it can be changed into a prime (20213747) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 505324 + ... + 505363.

It is an arithmetic number, because the mean of its divisors is an integer number (3537408).

Almost surely, 2^20213740 is an apocalyptic number.

20213740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20213740 is an abundant number, since it is smaller than the sum of its proper divisors (22235156).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20213740 is a wasteful number, since it uses less digits than its factorization.

20213740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1010696 (or 1010694 counting only the distinct ones).

The product of its (nonzero) digits is 336, while the sum is 19.

The square root of 20213740 is about 4495.9693059450. The cubic root of 20213740 is about 272.4053033469.

Adding to 20213740 its reverse (4731202), we get a palindrome (24944942).

The spelling of 20213740 in words is "twenty million, two hundred thirteen thousand, seven hundred forty".