1988072081 has 4 divisors (see below), whose sum is σ = 1988240100. Its totient is φ = 1987904064.

The previous prime is 1988072033. The next prime is 1988072101. The reversal of 1988072081 is 1802708891.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1802708891 = 19577 ⋅92083.

It can be written as a sum of positive squares in 2 ways, for example, as 198359056 + 1789713025 = 14084^2 + 42305^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1988072081 is a prime.

It is a super-2 number, since 2×1988072081² = 7904861198503341122, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1988072981) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 64796 + ... + 90413.

It is an arithmetic number, because the mean of its divisors is an integer number (497060025).

Almost surely, 2^1988072081 is an apocalyptic number.

It is an amenable number.

1988072081 is a deficient number, since it is larger than the sum of its proper divisors (168019).

1988072081 is a wasteful number, since it uses less digits than its factorization.

1988072081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 168018.

The product of its (nonzero) digits is 64512, while the sum is 44.

The square root of 1988072081 is about 44587.8019305729. The cubic root of 1988072081 is about 1257.4113479709.

The spelling of 1988072081 in words is "one billion, nine hundred eighty-eight million, seventy-two thousand, eighty-one".