20537621 has 8 divisors (see below), whose sum is σ = 22153824. Its totient is φ = 18926640.

The previous prime is 20537599. The next prime is 20537633. The reversal of 20537621 is 12673502.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20537621 - 2¹⁰ = 20536597 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20537021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11810 + ... + 13436.

It is an arithmetic number, because the mean of its divisors is an integer number (2769228).

Almost surely, 2^20537621 is an apocalyptic number.

It is an amenable number.

20537621 is a deficient number, since it is larger than the sum of its proper divisors (1616203).

20537621 is a wasteful number, since it uses less digits than its factorization.

20537621 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2611.

The product of its (nonzero) digits is 2520, while the sum is 26.

The square root of 20537621 is about 4531.8452091836. The cubic root of 20537621 is about 273.8525011093.

The spelling of 20537621 in words is "twenty million, five hundred thirty-seven thousand, six hundred twenty-one".