80987781 has 8 divisors (see below), whose sum is σ = 123409984. Its totient is φ = 46278720.

The previous prime is 80987741. The next prime is 80987827. The reversal of 80987781 is 18778908.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 80987781 - 2¹³ = 80979589 is a prime.

It is a super-2 number, since 2×80987781² = 13118041342607922, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 80987781.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (80987741) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1928260 + ... + 1928301.

It is an arithmetic number, because the mean of its divisors is an integer number (15426248).

Almost surely, 2^80987781 is an apocalyptic number.

It is an amenable number.

80987781 is a deficient number, since it is larger than the sum of its proper divisors (42422203).

80987781 is a wasteful number, since it uses less digits than its factorization.

80987781 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3856571.

The product of its (nonzero) digits is 225792, while the sum is 48.

The square root of 80987781 is about 8999.3211410639. The cubic root of 80987781 is about 432.6531133963.

The spelling of 80987781 in words is "eighty million, nine hundred eighty-seven thousand, seven hundred eighty-one".