20940621 has 24 divisors (see below), whose sum is σ = 30603456. Its totient is φ = 12729600.

The previous prime is 20940611. The next prime is 20940637. The reversal of 20940621 is 12604902.

It is a de Polignac number, because none of the positive numbers 2^k-20940621 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20940591 and 20940600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20940611) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 52021 + ... + 52421.

It is an arithmetic number, because the mean of its divisors is an integer number (1275144).

Almost surely, 2^20940621 is an apocalyptic number.

It is an amenable number.

20940621 is a deficient number, since it is larger than the sum of its proper divisors (9662835).

20940621 is a wasteful number, since it uses less digits than its factorization.

20940621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 533 (or 520 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 24.

The square root of 20940621 is about 4576.0923286140. The cubic root of 20940621 is about 275.6321369905.

The spelling of 20940621 in words is "twenty million, nine hundred forty thousand, six hundred twenty-one".