80305632781 has 4 divisors (see below), whose sum is σ = 87606144864. Its totient is φ = 73005120700.

The previous prime is 80305632709. The next prime is 80305632793. The reversal of 80305632781 is 18723650308.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 80305632781 - 2²⁷ = 80171415053 is a prime.

It is a super-2 number, since 2×80305632781² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (80305632581) 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, 3650256025 + ... + 3650256046.

It is an arithmetic number, because the mean of its divisors is an integer number (21901536216).

Almost surely, 2^80305632781 is an apocalyptic number.

80305632781 is the 126733-rd centered decagonal number.

It is an amenable number.

80305632781 is a deficient number, since it is larger than the sum of its proper divisors (7300512083).

80305632781 is a wasteful number, since it uses less digits than its factorization.

80305632781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7300512082.

The product of its (nonzero) digits is 241920, while the sum is 43.

The spelling of 80305632781 in words is "eighty billion, three hundred five million, six hundred thirty-two thousand, seven hundred eighty-one".