1947988081 has 16 divisors (see below), whose sum is σ = 2113026048. Its totient is φ = 1785168000.

The previous prime is 1947988079. The next prime is 1947988093. The reversal of 1947988081 is 1808897491.

It is a cyclic number.

It is not a de Polignac number, because 1947988081 - 2¹ = 1947988079 is a prime.

It is a super-2 number, since 2×1947988081² = 7589315127436125122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1947988051) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1691856 + ... + 1693006.

It is an arithmetic number, because the mean of its divisors is an integer number (132064128).

Almost surely, 2^1947988081 is an apocalyptic number.

It is an amenable number.

1947988081 is a deficient number, since it is larger than the sum of its proper divisors (165037967).

1947988081 is a wasteful number, since it uses less digits than its factorization.

1947988081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1992.

The product of its (nonzero) digits is 1161216, while the sum is 55.

The square root of 1947988081 is about 44136.0179558600. The cubic root of 1947988081 is about 1248.9031617849.

The spelling of 1947988081 in words is "one billion, nine hundred forty-seven million, nine hundred eighty-eight thousand, eighty-one".