1500121800 has 144 divisors (see below), whose sum is σ = 5054901540. Its totient is φ = 398684160.

The previous prime is 1500121793. The next prime is 1500121811. The reversal of 1500121800 is 81210051.

It can be written as a sum of positive squares in 6 ways, for example, as 552344004 + 947777796 = 23502^2 + 30786^2 .

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

It is an unprimeable number.

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 35 ways as a sum of consecutive naturals, for example, 605364 + ... + 607836.

Almost surely, 2^1500121800 is an apocalyptic number.

1500121800 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 1500121800, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2527450770).

1500121800 is an abundant number, since it is smaller than the sum of its proper divisors (3554779740).

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

1500121800 is a wasteful number, since it uses less digits than its factorization.

1500121800 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2832 (or 2820 counting only the distinct ones).

The product of its (nonzero) digits is 80, while the sum is 18.

The square root of 1500121800 is about 38731.4058613937. The cubic root of 1500121800 is about 1144.7452253136.

Adding to 1500121800 its reverse (81210051), we get a palindrome (1581331851).

The spelling of 1500121800 in words is "one billion, five hundred million, one hundred twenty-one thousand, eight hundred".