1261158400 has 90 divisors (see below), whose sum is σ = 3128593160. Its totient is φ = 504299520.

The previous prime is 1261158397. The next prime is 1261158407. The reversal of 1261158400 is 48511621.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1261158407) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 408061 + ... + 411139.

Almost surely, 2^1261158400 is an apocalyptic number.

1261158400 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 1261158400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1564296580).

1261158400 is an abundant number, since it is smaller than the sum of its proper divisors (1867434760).

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

1261158400 is an frugal number, since it uses more digits than its factorization.

1261158400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3117 (or 3086 counting only the distinct ones).

The product of its (nonzero) digits is 1920, while the sum is 28.

The square root of 1261158400 is about 35512.7920614530. The cubic root of 1261158400 is about 1080.4131935208.

The spelling of 1261158400 in words is "one billion, two hundred sixty-one million, one hundred fifty-eight thousand, four hundred".