31403430 has 64 divisors (see below), whose sum is σ = 84602880. Its totient is φ = 8288352.

The previous prime is 31403419. The next prime is 31403431. The reversal of 31403430 is 3430413.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31403431) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 28347 + ... + 29433.

It is an arithmetic number, because the mean of its divisors is an integer number (1321920).

Almost surely, 2^31403430 is an apocalyptic number.

31403430 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 31403430, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42301440).

31403430 is an abundant number, since it is smaller than the sum of its proper divisors (53199450).

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

31403430 is a wasteful number, since it uses less digits than its factorization.

31403430 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1210 (or 1204 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 18.

The square root of 31403430 is about 5603.8763369653. The cubic root of 31403430 is about 315.4949136171.

Adding to 31403430 its reverse (3430413), we get a palindrome (34833843).

The spelling of 31403430 in words is "thirty-one million, four hundred three thousand, four hundred thirty".