81598938037 has 4 divisors (see below), whose sum is σ = 81693931840. Its totient is φ = 81503944236.

The previous prime is 81598938023. The next prime is 81598938059. The reversal of 81598938037 is 73083989518.

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 81598938037 - 2¹⁹ = 81598413749 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (81598938077) 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, 47495613 + ... + 47497330.

It is an arithmetic number, because the mean of its divisors is an integer number (20423482960).

Almost surely, 2^81598938037 is an apocalyptic number.

It is an amenable number.

81598938037 is a deficient number, since it is larger than the sum of its proper divisors (94993803).

81598938037 is an equidigital number, since it uses as much as digits as its factorization.

81598938037 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 94993802.

The product of its (nonzero) digits is 13063680, while the sum is 61.

The spelling of 81598938037 in words is "eighty-one billion, five hundred ninety-eight million, nine hundred thirty-eight thousand, thirty-seven".