81802620939 has 32 divisors (see below), whose sum is σ = 125879814144. Its totient is φ = 46849968000.

The previous prime is 81802620929. The next prime is 81802620979. The reversal of 81802620939 is 93902620818.

It is not a de Polignac number, because 81802620939 - 2⁷ = 81802620811 is a prime.

It is not an unprimeable number, because it can be changed into a prime (81802620929) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 1199187 + ... + 1265564.

It is an arithmetic number, because the mean of its divisors is an integer number (3933744192).

Almost surely, 2^81802620939 is an apocalyptic number.

81802620939 is a deficient number, since it is larger than the sum of its proper divisors (44077193205).

81802620939 is a wasteful number, since it uses less digits than its factorization.

81802620939 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2464827.

The product of its (nonzero) digits is 373248, while the sum is 48.

The spelling of 81802620939 in words is "eighty-one billion, eight hundred two million, six hundred twenty thousand, nine hundred thirty-nine".