1311023100 has 72 divisors (see below), whose sum is σ = 3799947760. Its totient is φ = 348986880.

The previous prime is 1311023099. The next prime is 1311023107. The reversal of 1311023100 is 13201131.

It is a super-2 number, since 2×1311023100² = 3437563137467220000, which contains 22 as substring.

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 (1311023107) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 180336 + ... + 187464.

Almost surely, 2^1311023100 is an apocalyptic number.

1311023100 is a gapful number since it is divisible by the number (10) 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 1311023100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1899973880).

1311023100 is an abundant number, since it is smaller than the sum of its proper divisors (2488924660).

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

1311023100 is a wasteful number, since it uses less digits than its factorization.

1311023100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7759 (or 7752 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 12.

The square root of 1311023100 is about 36208.0529716802. The cubic root of 1311023100 is about 1094.4689570715.

Adding to 1311023100 its reverse (13201131), we get a palindrome (1324224231).

The spelling of 1311023100 in words is "one billion, three hundred eleven million, twenty-three thousand, one hundred".