71820033157 has 4 divisors (see below), whose sum is σ = 71838561676. Its totient is φ = 71801504640.

The previous prime is 71820033121. The next prime is 71820033217. The reversal of 71820033157 is 75133002817.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 53801266401 + 18018766756 = 231951^2 + 134234^2 .

It is a cyclic number.

It is not a de Polignac number, because 71820033157 - 2¹¹ = 71820031109 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 (71820033557) 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, 9258444 + ... + 9266197.

It is an arithmetic number, because the mean of its divisors is an integer number (17959640419).

Almost surely, 2^71820033157 is an apocalyptic number.

It is an amenable number.

71820033157 is a deficient number, since it is larger than the sum of its proper divisors (18528519).

71820033157 is a wasteful number, since it uses less digits than its factorization.

71820033157 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18528518.

The product of its (nonzero) digits is 35280, while the sum is 37.

The spelling of 71820033157 in words is "seventy-one billion, eight hundred twenty million, thirty-three thousand, one hundred fifty-seven".