1891530816 has 56 divisors (see below), whose sum is σ = 5719632960. Its totient is φ = 540436992.

The previous prime is 1891530799. The next prime is 1891530821. The reversal of 1891530816 is 6180351981.

It is a tau number, because it is divible by the number of its divisors (56).

It is a Harshad number since it is a multiple of its sum of digits (42).

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 702351 + ... + 705038.

Almost surely, 2^1891530816 is an apocalyptic number.

1891530816 is a gapful number since it is divisible by the number (16) formed by its first and last digit.

It is an amenable number.

1891530816 is an abundant number, since it is smaller than the sum of its proper divisors (3828102144).

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

1891530816 is a wasteful number, since it uses less digits than its factorization.

1891530816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1407411 (or 1407401 counting only the distinct ones).

The product of its (nonzero) digits is 51840, while the sum is 42.

The square root of 1891530816 is about 43491.7327316353. The cubic root of 1891530816 is about 1236.7193056529.

The spelling of 1891530816 in words is "one billion, eight hundred ninety-one million, five hundred thirty thousand, eight hundred sixteen".