1211270400 has 324 divisors, whose sum is σ = 4589010972. Its totient is φ = 303759360.

The previous prime is 1211270353. The next prime is 1211270419. The reversal of 1211270400 is 40721121.

It can be written as a sum of positive squares in 6 ways, for example, as 23503104 + 1187767296 = 4848^2 + 34464^2 .

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 978582 + ... + 979818.

Almost surely, 2^1211270400 is an apocalyptic number.

1211270400 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 1211270400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2294505486).

1211270400 is an abundant number, since it is smaller than the sum of its proper divisors (3377740572).

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

1211270400 is a wasteful number, since it uses less digits than its factorization.

1211270400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1286 (or 1264 counting only the distinct ones).

The product of its (nonzero) digits is 112, while the sum is 18.

The square root of 1211270400 is about 34803.3101873945. The cubic root of 1211270400 is about 1065.9750377544.

Adding to 1211270400 its reverse (40721121), we get a palindrome (1251991521).

The spelling of 1211270400 in words is "one billion, two hundred eleven million, two hundred seventy thousand, four hundred".