20311400 has 48 divisors (see below), whose sum is σ = 48395340. Its totient is φ = 7923200.

The previous prime is 20311381. The next prime is 20311433. The reversal of 20311400 is 411302.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 2553604 + 17757796 = 1598^2 + 4214^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6962 + ... + 9438.

Almost surely, 2^20311400 is an apocalyptic number.

20311400 is a gapful number since it is divisible by the number (20) 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 20311400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24197670).

20311400 is an abundant number, since it is smaller than the sum of its proper divisors (28083940).

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

20311400 is a wasteful number, since it uses less digits than its factorization.

20311400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2534 (or 2525 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 11.

The square root of 20311400 is about 4506.8170586346. The cubic root of 20311400 is about 272.8432954162.

Adding to 20311400 its reverse (411302), we get a palindrome (20722702).

The spelling of 20311400 in words is "twenty million, three hundred eleven thousand, four hundred".