189424373581 has 4 divisors (see below), whose sum is σ = 189500973052. Its totient is φ = 189347774112.

The previous prime is 189424373561. The next prime is 189424373617. The reversal of 189424373581 is 185373424981.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 185373424981 = 2423 ⋅76505747.

It can be written as a sum of positive squares in 2 ways, for example, as 93752316100 + 95672057481 = 306190^2 + 309309^2 .

It is a cyclic number.

It is not a de Polignac number, because 189424373581 - 2⁹ = 189424373069 is a prime.

It is a super-2 number, since 2×189424373581² (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 (189424373561) 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, 38296026 + ... + 38300971.

It is an arithmetic number, because the mean of its divisors is an integer number (47375243263).

Almost surely, 2^189424373581 is an apocalyptic number.

It is an amenable number.

189424373581 is a deficient number, since it is larger than the sum of its proper divisors (76599471).

189424373581 is an equidigital number, since it uses as much as digits as its factorization.

189424373581 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76599470.

The product of its digits is 5806080, while the sum is 55.

The spelling of 189424373581 in words is "one hundred eighty-nine billion, four hundred twenty-four million, three hundred seventy-three thousand, five hundred eighty-one".