31400400 has 120 divisors (see below), whose sum is σ = 101850624. Its totient is φ = 8268800.

The previous prime is 31400399. The next prime is 31400401. The reversal of 31400400 is 400413.

It is an interprime number because it is at equal distance from previous prime (31400399) and next prime (31400401).

It is a tau number, because it is divible by the number of its divisors (120).

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (31400401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 164305 + ... + 164495.

Almost surely, 2^31400400 is an apocalyptic number.

31400400 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 31400400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (50925312).

31400400 is an abundant number, since it is smaller than the sum of its proper divisors (70450224).

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

31400400 is a wasteful number, since it uses less digits than its factorization.

31400400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 349 (or 338 counting only the distinct ones).

The product of its (nonzero) digits is 48, while the sum is 12.

The square root of 31400400 is about 5603.6059818656. The cubic root of 31400400 is about 315.4847663143.

Adding to 31400400 its reverse (400413), we get a palindrome (31800813).

The spelling of 31400400 in words is "thirty-one million, four hundred thousand, four hundred".