1297818900 has 162 divisors, whose sum is σ = 4732255710. Its totient is φ = 296634240.

The previous prime is 1297818887. The next prime is 1297818901. The reversal of 1297818900 is 98187921.

It can be written as a sum of positive squares in 3 ways, for example, as 308213136 + 989605764 = 17556^2 + 31458^2 .

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1297818901) by changing a digit.

It is a polite number, since it can be written in 53 ways as a sum of consecutive naturals, for example, 29386 + ... + 58814.

It is an arithmetic number, because the mean of its divisors is an integer number (29211455).

Almost surely, 2^1297818900 is an apocalyptic number.

1297818900 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 1297818900, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2366127855).

1297818900 is an abundant number, since it is smaller than the sum of its proper divisors (3434436810).

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

1297818900 is a wasteful number, since it uses less digits than its factorization.

1297818900 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29463 (or 29446 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 45.

The square root of 1297818900 is about 36025.2536424103. The cubic root of 1297818900 is about 1090.7821729241.

It can be divided in two parts, 12978 and 18900, that added together give a triangular number (31878 = T₂₅₂).

The spelling of 1297818900 in words is "one billion, two hundred ninety-seven million, eight hundred eighteen thousand, nine hundred".