638637542 has 16 divisors (see below), whose sum is σ = 965790000. Its totient is φ = 316714080.

The previous prime is 638637529. The next prime is 638637569. The reversal of 638637542 is 245736836.

It is a junction number, because it is equal to n+sod(n) for n = 638637493 and 638637502.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 303209 + ... + 305307.

It is an arithmetic number, because the mean of its divisors is an integer number (60361875).

Almost surely, 2^638637542 is an apocalyptic number.

638637542 is a deficient number, since it is larger than the sum of its proper divisors (327152458).

638637542 is a wasteful number, since it uses less digits than its factorization.

638637542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3271.

The product of its digits is 725760, while the sum is 44.

The square root of 638637542 is about 25271.2789941467. The cubic root of 638637542 is about 861.1619151391.

The spelling of 638637542 in words is "six hundred thirty-eight million, six hundred thirty-seven thousand, five hundred forty-two".