1156638 has 16 divisors (see below), whose sum is σ = 2643840. Its totient is φ = 330456.

The previous prime is 1156637. The next prime is 1156643. The reversal of 1156638 is 8366511.

It is a super-2 number, since 2×1156638² = 2675622926088, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1156633) 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, 13728 + ... + 13811.

It is an arithmetic number, because the mean of its divisors is an integer number (165240).

2^1156638 is an apocalyptic number.

1156638 is an abundant number, since it is smaller than the sum of its proper divisors (1487202).

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

1156638 is a wasteful number, since it uses less digits than its factorization.

1156638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27551.

The product of its digits is 4320, while the sum is 30.

The square root of 1156638 is about 1075.4710595827. The cubic root of 1156638 is about 104.9701502452.

The spelling of 1156638 in words is "one million, one hundred fifty-six thousand, six hundred thirty-eight".