838642644 has 54 divisors (see below), whose sum is σ = 2466013914. Its totient is φ = 239611680.

The previous prime is 838642643. The next prime is 838642663. The reversal of 838642644 is 446246838.

838642644 is a `hidden beast` number, since 8 + 386 + 4 + 264 + 4 = 666.

It can be written as a sum of positive squares in only one way, i.e., 512479044 + 326163600 = 22638^2 + 18060^2 .

It is a super-4 number, since 4×838642644⁴ (a number of 37 digits) contains 4444 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 838642644.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (838642643) by changing a digit.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 235947 + ... + 239474.

Almost surely, 2^838642644 is an apocalyptic number.

838642644 is a gapful number since it is divisible by the number (84) formed by its first and last digit.

It is an amenable number.

838642644 is an abundant number, since it is smaller than the sum of its proper divisors (1627371270).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

838642644 is a wasteful number, since it uses less digits than its factorization.

838642644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 475445 (or 475433 counting only the distinct ones).

The product of its digits is 884736, while the sum is 45.

The square root of 838642644 is about 28959.3274093167. The cubic root of 838642644 is about 943.0303006254.

The spelling of 838642644 in words is "eight hundred thirty-eight million, six hundred forty-two thousand, six hundred forty-four".