16621037 has 2 divisors, whose sum is σ = 16621038. Its totient is φ = 16621036.

The previous prime is 16621021. The next prime is 16621039. The reversal of 16621037 is 73012661.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 13734436 + 2886601 = 3706^2 + 1699^2 .

It is an emirp because it is prime and its reverse (73012661) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 16621037 - 2⁴ = 16621021 is a prime.

Together with 16621039, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p_1068470 and since 16621037 and 1068470 have the same sum of digits, it is a Honaker prime.

It is a junction number, because it is equal to n+sod(n) for n = 16620997 and 16621015.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (16621039) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8310518 + 8310519.

It is an arithmetic number, because the mean of its divisors is an integer number (8310519).

Almost surely, 2^16621037 is an apocalyptic number.

It is an amenable number.

16621037 is a deficient number, since it is larger than the sum of its proper divisors (1).

16621037 is an equidigital number, since it uses as much as digits as its factorization.

16621037 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1512, while the sum is 26.

The square root of 16621037 is about 4076.8906043700. The cubic root of 16621037 is about 255.2031547796.

Adding to 16621037 its reverse (73012661), we get a palindrome (89633698).

The spelling of 16621037 in words is "sixteen million, six hundred twenty-one thousand, thirty-seven".