38213521 has 4 divisors (see below), whose sum is σ = 38257972. Its totient is φ = 38169072.

The previous prime is 38213507. The next prime is 38213531. The reversal of 38213521 is 12531283.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 12852225 + 25361296 = 3585^2 + 5036^2 .

It is a cyclic number.

It is not a de Polignac number, because 38213521 - 2²¹ = 36116369 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (38213531) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 20910 + ... + 22663.

It is an arithmetic number, because the mean of its divisors is an integer number (9564493).

Almost surely, 2^38213521 is an apocalyptic number.

It is an amenable number.

38213521 is a deficient number, since it is larger than the sum of its proper divisors (44451).

38213521 is an equidigital number, since it uses as much as digits as its factorization.

38213521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 44450.

The product of its digits is 1440, while the sum is 25.

The square root of 38213521 is about 6181.7085825846. The cubic root of 38213521 is about 336.8260599792.

The spelling of 38213521 in words is "thirty-eight million, two hundred thirteen thousand, five hundred twenty-one".