20663740 has 24 divisors (see below), whose sum is σ = 43711920. Its totient is φ = 8204928.

The previous prime is 20663737. The next prime is 20663759. The reversal of 20663740 is 4736602.

It is a junction number, because it is equal to n+sod(n) for n = 20663699 and 20663708.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 937 + ... + 6496.

It is an arithmetic number, because the mean of its divisors is an integer number (1821330).

Almost surely, 2^20663740 is an apocalyptic number.

20663740 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20663740 is an abundant number, since it is smaller than the sum of its proper divisors (23048180).

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

20663740 is a wasteful number, since it uses less digits than its factorization.

20663740 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7581 (or 7579 counting only the distinct ones).

The product of its (nonzero) digits is 6048, while the sum is 28.

The square root of 20663740 is about 4545.7386638477. The cubic root of 20663740 is about 274.4119223769.

The spelling of 20663740 in words is "twenty million, six hundred sixty-three thousand, seven hundred forty".