1642101881 has 4 divisors (see below), whose sum is σ = 1876687872. Its totient is φ = 1407515892.

The previous prime is 1642101833. The next prime is 1642101907. The reversal of 1642101881 is 1881012461.

It is a happy number.

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 1642101881 - 2¹⁸ = 1641839737 is a prime.

It is a super-2 number, since 2×1642101881² = 5392997175167476322, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1642109881) 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, 117292985 + ... + 117292998.

It is an arithmetic number, because the mean of its divisors is an integer number (469171968).

Almost surely, 2^1642101881 is an apocalyptic number.

It is an amenable number.

1642101881 is a deficient number, since it is larger than the sum of its proper divisors (234585991).

1642101881 is an equidigital number, since it uses as much as digits as its factorization.

1642101881 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 234585990.

The product of its (nonzero) digits is 3072, while the sum is 32.

The square root of 1642101881 is about 40522.8562788952. The cubic root of 1642101881 is about 1179.7772923086. Note that the first 3 decimals are identical.

The spelling of 1642101881 in words is "one billion, six hundred forty-two million, one hundred one thousand, eight hundred eighty-one".