16250021 has 8 divisors (see below), whose sum is σ = 16447320. Its totient is φ = 16054272.

The previous prime is 16250009. The next prime is 16250023. The reversal of 16250021 is 12005261.

It can be written as a sum of positive squares in 4 ways, for example, as 1999396 + 14250625 = 1414^2 + 3775^2 .

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 16250021 - 2¹⁸ = 15987877 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 (16250023) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 51761 + ... + 52073.

It is an arithmetic number, because the mean of its divisors is an integer number (2055915).

Almost surely, 2^16250021 is an apocalyptic number.

It is an amenable number.

16250021 is a deficient number, since it is larger than the sum of its proper divisors (197299).

16250021 is a wasteful number, since it uses less digits than its factorization.

16250021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 775.

The product of its (nonzero) digits is 120, while the sum is 17.

The square root of 16250021 is about 4031.1314788779. The cubic root of 16250021 is about 253.2899600645.

Adding to 16250021 its reverse (12005261), we get a palindrome (28255282).

The spelling of 16250021 in words is "sixteen million, two hundred fifty thousand, twenty-one".