309421040 has 20 divisors (see below), whose sum is σ = 719404104. Its totient is φ = 123768384.

The previous prime is 309421009. The next prime is 309421043. The reversal of 309421040 is 40124903.

It is a tau number, because it is divible by the number of its divisors (20).

It is a junction number, because it is equal to n+sod(n) for n = 309420997 and 309421015.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (309421043) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1933802 + ... + 1933961.

Almost surely, 2^309421040 is an apocalyptic number.

It is an amenable number.

309421040 is an abundant number, since it is smaller than the sum of its proper divisors (409983064).

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

309421040 is a wasteful number, since it uses less digits than its factorization.

309421040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3867776 (or 3867770 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 23.

The square root of 309421040 is about 17590.3678187808. The cubic root of 309421040 is about 676.3683554347.

Adding to 309421040 its reverse (40124903), we get a palindrome (349545943).

The spelling of 309421040 in words is "three hundred nine million, four hundred twenty-one thousand, forty".