31201020 has 72 divisors (see below), whose sum is σ = 95672304. Its totient is φ = 8229888.

The previous prime is 31201007. The next prime is 31201039. The reversal of 31201020 is 2010213.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a junction number, because it is equal to n+sod(n) for n = 31200993 and 31201011.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 16567 + ... + 18353.

It is an arithmetic number, because the mean of its divisors is an integer number (1328782).

Almost surely, 2^31201020 is an apocalyptic number.

31201020 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 31201020, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47836152).

31201020 is an abundant number, since it is smaller than the sum of its proper divisors (64471284).

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

31201020 is a wasteful number, since it uses less digits than its factorization.

31201020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1899 (or 1894 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 9.

The square root of 31201020 is about 5585.7873214078. The cubic root of 31201020 is about 314.8156139345.

Adding to 31201020 its reverse (2010213), we get a palindrome (33211233).

The spelling of 31201020 in words is "thirty-one million, two hundred one thousand, twenty".