1245399100 has 72 divisors (see below), whose sum is σ = 2956060800. Its totient is φ = 451665600.

The previous prime is 1245399097. The next prime is 1245399109. The reversal of 1245399100 is 19935421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1245399109) 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, 481611 + ... + 484189.

It is an arithmetic number, because the mean of its divisors is an integer number (41056400).

Almost surely, 2^1245399100 is an apocalyptic number.

1245399100 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 1245399100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1478030400).

1245399100 is an abundant number, since it is smaller than the sum of its proper divisors (1710661700).

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

1245399100 is a wasteful number, since it uses less digits than its factorization.

1245399100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3043 (or 3036 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 34.

The square root of 1245399100 is about 35290.2125241546. The cubic root of 1245399100 is about 1075.8940750147.

The spelling of 1245399100 in words is "one billion, two hundred forty-five million, three hundred ninety-nine thousand, one hundred".