7491128400 has 240 divisors, whose sum is σ = 30472156800. Its totient is φ = 1712240640.

The previous prime is 7491128389. The next prime is 7491128419. The reversal of 7491128400 is 48211947.

7491128400 is a `hidden beast` number, since 7 + 491 + 128 + 40 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (240).

It is a super-2 number, since 2×7491128400² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

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, 26056 + ... + 125144.

It is an arithmetic number, because the mean of its divisors is an integer number (126967320).

Almost surely, 2^7491128400 is an apocalyptic number.

7491128400 is a gapful number since it is divisible by the number (70) 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 7491128400, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15236078400).

7491128400 is an abundant number, since it is smaller than the sum of its proper divisors (22981028400).

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

7491128400 is a wasteful number, since it uses less digits than its factorization.

7491128400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 99123 (or 99106 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 7491128400 is about 86551.3050161579. The cubic root of 7491128400 is about 1956.6617129616.

The spelling of 7491128400 in words is "seven billion, four hundred ninety-one million, one hundred twenty-eight thousand, four hundred".