30121686 has 32 divisors (see below), whose sum is σ = 76500480. Its totient is φ = 8606088.

The previous prime is 30121681. The next prime is 30121687. The reversal of 30121686 is 68612103.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30121681) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 39466 + ... + 40221.

It is an arithmetic number, because the mean of its divisors is an integer number (2390640).

Almost surely, 2^30121686 is an apocalyptic number.

30121686 is an abundant number, since it is smaller than the sum of its proper divisors (46378794).

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

30121686 is a wasteful number, since it uses less digits than its factorization.

30121686 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 79705 (or 79699 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 30121686 is about 5488.3226945944. The cubic root of 30121686 is about 311.1428023934.

Adding to 30121686 its reverse (68612103), we get a palindrome (98733789).

The spelling of 30121686 in words is "thirty million, one hundred twenty-one thousand, six hundred eighty-six".