1211402400 has 288 divisors, whose sum is σ = 4354596288. Its totient is φ = 290611200.

The previous prime is 1211402389. The next prime is 1211402453. The reversal of 1211402400 is 42041121.

It is a super-3 number, since 3×1211402400³ (a number of 28 digits) contains 333 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 1211402400.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 1278727 + ... + 1279673.

It is an arithmetic number, because the mean of its divisors is an integer number (15120126).

Almost surely, 2^1211402400 is an apocalyptic number.

1211402400 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 1211402400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2177298144).

1211402400 is an abundant number, since it is smaller than the sum of its proper divisors (3143193888).

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

1211402400 is a wasteful number, since it uses less digits than its factorization.

1211402400 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1024 (or 1011 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

The square root of 1211402400 is about 34805.2065070730. The cubic root of 1211402400 is about 1066.0137584215.

Adding to 1211402400 its reverse (42041121), we get a palindrome (1253443521).

The spelling of 1211402400 in words is "one billion, two hundred eleven million, four hundred two thousand, four hundred".