11651638 has 4 divisors (see below), whose sum is σ = 17477460. Its totient is φ = 5825818.

The previous prime is 11651621. The next prime is 11651657. The reversal of 11651638 is 83615611.

11651638 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 83615611 = 83 ⋅1007417.

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, 2912908 + ... + 2912911.

It is an arithmetic number, because the mean of its divisors is an integer number (4369365).

Almost surely, 2^11651638 is an apocalyptic number.

11651638 is a deficient number, since it is larger than the sum of its proper divisors (5825822).

11651638 is an equidigital number, since it uses as much as digits as its factorization.

11651638 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5825821.

The product of its digits is 4320, while the sum is 31.

The square root of 11651638 is about 3413.4495748436. The cubic root of 11651638 is about 226.7056416063.

The spelling of 11651638 in words is "eleven million, six hundred fifty-one thousand, six hundred thirty-eight".