30431220 has 48 divisors (see below), whose sum is σ = 85561728. Its totient is φ = 8081280.

The previous prime is 30431209. The next prime is 30431221. The reversal of 30431220 is 2213403.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 30431220.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (30431221) 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, 15705 + ... + 17535.

It is an arithmetic number, because the mean of its divisors is an integer number (1782536).

Almost surely, 2^30431220 is an apocalyptic number.

30431220 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

30431220 is an abundant number, since it is smaller than the sum of its proper divisors (55130508).

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

30431220 is a wasteful number, since it uses less digits than its factorization.

30431220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2120 (or 2118 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 15.

The square root of 30431220 is about 5516.4499453906. The cubic root of 30431220 is about 312.2049524512.

Adding to 30431220 its reverse (2213403), we get a palindrome (32644623).

The spelling of 30431220 in words is "thirty million, four hundred thirty-one thousand, two hundred twenty".