451491840 has 384 divisors, whose sum is σ = 1698278400. Its totient is φ = 113541120.

The previous prime is 451491829. The next prime is 451491847. The reversal of 451491840 is 48194154.

It is a tau number, because it is divible by the number of its divisors (384).

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

It is a junction number, because it is equal to n+sod(n) for n = 451491795 and 451491804.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (451491847) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 6359005 + ... + 6359075.

It is an arithmetic number, because the mean of its divisors is an integer number (4422600).

Almost surely, 2^451491840 is an apocalyptic number.

451491840 is a gapful number since it is divisible by the number (40) 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 451491840, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (849139200).

451491840 is an abundant number, since it is smaller than the sum of its proper divisors (1246786560).

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

451491840 is a wasteful number, since it uses less digits than its factorization.

451491840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 130 (or 104 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The square root of 451491840 is about 21248.3373467196. The cubic root of 451491840 is about 767.1553213275.

The spelling of 451491840 in words is "four hundred fifty-one million, four hundred ninety-one thousand, eight hundred forty".