190643381 has 4 divisors (see below), whose sum is σ = 195076992. Its totient is φ = 186209772.

The previous prime is 190643363. The next prime is 190643407. The reversal of 190643381 is 183346091.

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, and also an emirpimes, since its reverse is a distinct semiprime: 183346091 = 29 ⋅6322279.

It is a cyclic number.

It is not a de Polignac number, because 190643381 - 2²² = 186449077 is a prime.

It is a super-2 number, since 2×190643381² = 72689797438222322, which 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 (190643081) 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, 2216741 + ... + 2216826.

It is an arithmetic number, because the mean of its divisors is an integer number (48769248).

Almost surely, 2^190643381 is an apocalyptic number.

It is an amenable number.

190643381 is a deficient number, since it is larger than the sum of its proper divisors (4433611).

190643381 is an equidigital number, since it uses as much as digits as its factorization.

190643381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4433610.

The product of its (nonzero) digits is 15552, while the sum is 35.

The square root of 190643381 is about 13807.3669104576. The cubic root of 190643381 is about 575.5378770326.

The spelling of 190643381 in words is "one hundred ninety million, six hundred forty-three thousand, three hundred eighty-one".