491557770 has 96 divisors (see below), whose sum is σ = 1400877504. Its totient is φ = 118598400.

The previous prime is 491557751. The next prime is 491557777. The reversal of 491557770 is 77755194.

491557770 is a `hidden beast` number, since 4 + 9 + 1 + 5 + 577 + 70 = 666.

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

It is not an unprimeable number, because it can be changed into a prime (491557777) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 229605 + ... + 231735.

It is an arithmetic number, because the mean of its divisors is an integer number (14592474).

Almost surely, 2^491557770 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 491557770, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (700438752).

491557770 is an abundant number, since it is smaller than the sum of its proper divisors (909319734).

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

491557770 is a wasteful number, since it uses less digits than its factorization.

491557770 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2388 (or 2385 counting only the distinct ones).

The product of its (nonzero) digits is 308700, while the sum is 45.

The square root of 491557770 is about 22171.1021376927. The cubic root of 491557770 is about 789.2080778578.

The spelling of 491557770 in words is "four hundred ninety-one million, five hundred fifty-seven thousand, seven hundred seventy".