31431020 has 12 divisors (see below), whose sum is σ = 66005184. Its totient is φ = 12572400.

The previous prime is 31431017. The next prime is 31431031. The reversal of 31431020 is 2013413.

It is a junction number, because it is equal to n+sod(n) for n = 31430986 and 31431004.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 785756 + ... + 785795.

It is an arithmetic number, because the mean of its divisors is an integer number (5500432).

Almost surely, 2^31431020 is an apocalyptic number.

It is an amenable number.

31431020 is an abundant number, since it is smaller than the sum of its proper divisors (34574164).

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

31431020 is a wasteful number, since it uses less digits than its factorization.

31431020 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1571560 (or 1571558 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 14.

The square root of 31431020 is about 5606.3374853821. The cubic root of 31431020 is about 315.5872809874.

Adding to 31431020 its reverse (2013413), we get a palindrome (33444433).

The spelling of 31431020 in words is "thirty-one million, four hundred thirty-one thousand, twenty".