3420921 has 8 divisors (see below), whose sum is σ = 5212864. Its totient is φ = 1954800.

The previous prime is 3420919. The next prime is 3420959. The reversal of 3420921 is 1290243.

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

It is not a de Polignac number, because 3420921 - 2¹ = 3420919 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21), and also a Moran number because the ratio is a prime number: 162901 = 3420921 / (3 + 4 + 2 + 0 + 9 + 2 + 1).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (3420121) 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, 81430 + ... + 81471.

It is an arithmetic number, because the mean of its divisors is an integer number (651608).

Almost surely, 2^3420921 is an apocalyptic number.

It is an amenable number.

3420921 is a deficient number, since it is larger than the sum of its proper divisors (1791943).

3420921 is a wasteful number, since it uses less digits than its factorization.

3420921 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 162911.

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 3420921 is about 1849.5731940099. The cubic root of 3420921 is about 150.6772487368.

The spelling of 3420921 in words is "three million, four hundred twenty thousand, nine hundred twenty-one".