451491217920 has 640 divisors, whose sum is σ = 1702062489600. Its totient is φ = 113121017856.

The previous prime is 451491217907. The next prime is 451491217943. The reversal of 451491217920 is 29712194154.

451491217920 is a `hidden beast` number, since 4 + 51 + 491 + 21 + 7 + 92 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (640).

It is a Harshad number since it is a multiple of its sum of digits (45).

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 166785207 + ... + 166787913.

It is an arithmetic number, because the mean of its divisors is an integer number (2659472640).

Almost surely, 2^451491217920 is an apocalyptic number.

451491217920 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 451491217920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (851031244800).

451491217920 is an abundant number, since it is smaller than the sum of its proper divisors (1250571271680).

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

451491217920 is a wasteful number, since it uses less digits than its factorization.

451491217920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2885 (or 2863 counting only the distinct ones).

The product of its (nonzero) digits is 181440, while the sum is 45.

The spelling of 451491217920 in words is "four hundred fifty-one billion, four hundred ninety-one million, two hundred seventeen thousand, nine hundred twenty".