840122621 has 8 divisors (see below), whose sum is σ = 906843000. Its totient is φ = 773701632.

The previous prime is 840122567. The next prime is 840122659. The reversal of 840122621 is 126221048.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 66504025 + 773618596 = 8155^2 + 27814^2 .

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 840122621 - 2¹⁴ = 840106237 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 (840122681) 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, 68996 + ... + 80253.

It is an arithmetic number, because the mean of its divisors is an integer number (113355375).

Almost surely, 2^840122621 is an apocalyptic number.

It is an amenable number.

840122621 is a deficient number, since it is larger than the sum of its proper divisors (66720379).

840122621 is a wasteful number, since it uses less digits than its factorization.

840122621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 149695.

The product of its (nonzero) digits is 1536, while the sum is 26.

The square root of 840122621 is about 28984.8688284077. The cubic root of 840122621 is about 943.5847056036.

Adding to 840122621 its reverse (126221048), we get a palindrome (966343669).

The spelling of 840122621 in words is "eight hundred forty million, one hundred twenty-two thousand, six hundred twenty-one".