840726421 has 8 divisors (see below), whose sum is σ = 885250080. Its totient is φ = 796230288.

The previous prime is 840726401. The next prime is 840726431. The reversal of 840726421 is 124627048.

It is a happy number.

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 840726421 - 2⁵ = 840726389 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 (840726401) 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, 93495 + ... + 102091.

It is an arithmetic number, because the mean of its divisors is an integer number (110656260).

Almost surely, 2^840726421 is an apocalyptic number.

It is an amenable number.

840726421 is a deficient number, since it is larger than the sum of its proper divisors (44523659).

840726421 is a wasteful number, since it uses less digits than its factorization.

840726421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13763.

The product of its (nonzero) digits is 21504, while the sum is 34.

The square root of 840726421 is about 28995.2827370247. The cubic root of 840726421 is about 943.8107043624.

The spelling of 840726421 in words is "eight hundred forty million, seven hundred twenty-six thousand, four hundred twenty-one".