7521638 has 4 divisors (see below), whose sum is σ = 11282460. Its totient is φ = 3760818.

The previous prime is 7521617. The next prime is 7521641. The reversal of 7521638 is 8361257.

It is a happy number.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1880408 + ... + 1880411.

It is an arithmetic number, because the mean of its divisors is an integer number (2820615).

Almost surely, 2^7521638 is an apocalyptic number.

7521638 is a deficient number, since it is larger than the sum of its proper divisors (3760822).

7521638 is a wasteful number, since it uses less digits than its factorization.

7521638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3760821.

The product of its digits is 10080, while the sum is 32.

The square root of 7521638 is about 2742.5604824689. The cubic root of 7521638 is about 195.9314455513.

The spelling of 7521638 in words is "seven million, five hundred twenty-one thousand, six hundred thirty-eight".