30121640 has 32 divisors (see below), whose sum is σ = 67932000. Its totient is φ = 12020544.

The previous prime is 30121639. The next prime is 30121643. The reversal of 30121640 is 4612103.

It is not an unprimeable number, because it can be changed into a prime (30121643) 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, 29051 + ... + 30069.

It is an arithmetic number, because the mean of its divisors is an integer number (2122875).

Almost surely, 2^30121640 is an apocalyptic number.

It is an amenable number.

30121640 is an abundant number, since it is smaller than the sum of its proper divisors (37810360).

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

30121640 is a wasteful number, since it uses less digits than its factorization.

30121640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1769 (or 1765 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

The square root of 30121640 is about 5488.3185038771. The cubic root of 30121640 is about 311.1426440072.

Adding to 30121640 its reverse (4612103), we get a palindrome (34733743).

The spelling of 30121640 in words is "thirty million, one hundred twenty-one thousand, six hundred forty".