11978658 has 16 divisors (see below), whose sum is σ = 26619360. Its totient is φ = 3992868.

The previous prime is 11978657. The next prime is 11978663. The reversal of 11978658 is 85687911.

It is not an unprimeable number, because it can be changed into a prime (11978651) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 110860 + ... + 110967.

It is an arithmetic number, because the mean of its divisors is an integer number (1663710).

Almost surely, 2^11978658 is an apocalyptic number.

11978658 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

11978658 is an abundant number, since it is smaller than the sum of its proper divisors (14640702).

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

11978658 is a wasteful number, since it uses less digits than its factorization.

11978658 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 221838 (or 221832 counting only the distinct ones).

The product of its digits is 120960, while the sum is 45.

The square root of 11978658 is about 3461.0197919110. The cubic root of 11978658 is about 228.8070430168.

The spelling of 11978658 in words is "eleven million, nine hundred seventy-eight thousand, six hundred fifty-eight".