20770167581 has 4 divisors (see below), whose sum is σ = 20832917664. Its totient is φ = 20707417500.

The previous prime is 20770167563. The next prime is 20770167643. The reversal of 20770167581 is 18576107702.

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 20770167581 - 2¹⁴ = 20770151197 is a prime.

It is a super-2 number, since 2×20770167581² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20770167511) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 31374545 + ... + 31375206.

It is an arithmetic number, because the mean of its divisors is an integer number (5208229416).

Almost surely, 2^20770167581 is an apocalyptic number.

It is an amenable number.

20770167581 is a deficient number, since it is larger than the sum of its proper divisors (62750083).

20770167581 is an equidigital number, since it uses as much as digits as its factorization.

20770167581 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62750082.

The product of its (nonzero) digits is 164640, while the sum is 44.

The spelling of 20770167581 in words is "twenty billion, seven hundred seventy million, one hundred sixty-seven thousand, five hundred eighty-one".