161421034021 has 8 divisors (see below), whose sum is σ = 181396212480. Its totient is φ = 142525594992.

The previous prime is 161421034007. The next prime is 161421034039. The reversal of 161421034021 is 120430124161.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 161421034021 - 2¹¹ = 161421031973 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 (161421034321) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 269934541 + ... + 269935138.

It is an arithmetic number, because the mean of its divisors is an integer number (22674526560).

Almost surely, 2^161421034021 is an apocalyptic number.

It is an amenable number.

161421034021 is a deficient number, since it is larger than the sum of its proper divisors (19975178459).

161421034021 is a wasteful number, since it uses less digits than its factorization.

161421034021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 539869715.

The product of its (nonzero) digits is 1152, while the sum is 25.

Adding to 161421034021 its reverse (120430124161), we get a palindrome (281851158182).

The spelling of 161421034021 in words is "one hundred sixty-one billion, four hundred twenty-one million, thirty-four thousand, twenty-one".