491251851552 has 384 divisors, whose sum is σ = 1731729162240. Its totient is φ = 118069539840.

The previous prime is 491251851539. The next prime is 491251851569. The reversal of 491251851552 is 255158152194.

It is a Harshad number since it is a multiple of its sum of digits (48).

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, 5998593 + ... + 6079935.

It is an arithmetic number, because the mean of its divisors is an integer number (4509711360).

Almost surely, 2^491251851552 is an apocalyptic number.

491251851552 is a gapful number since it is divisible by the number (42) 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 491251851552, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (865864581120).

491251851552 is an abundant number, since it is smaller than the sum of its proper divisors (1240477310688).

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

491251851552 is a wasteful number, since it uses less digits than its factorization.

491251851552 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 81436 (or 81428 counting only the distinct ones).

The product of its digits is 720000, while the sum is 48.

The spelling of 491251851552 in words is "four hundred ninety-one billion, two hundred fifty-one million, eight hundred fifty-one thousand, five hundred fifty-two".