3478979821 has 4 divisors (see below), whose sum is σ = 3480346144. Its totient is φ = 3477613500.

The previous prime is 3478979813. The next prime is 3478979863. The reversal of 3478979821 is 1289798743.

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 3478979821 - 2³ = 3478979813 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 (3478979921) 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, 679335 + ... + 684436.

It is an arithmetic number, because the mean of its divisors is an integer number (870086536).

Almost surely, 2^3478979821 is an apocalyptic number.

It is an amenable number.

3478979821 is a deficient number, since it is larger than the sum of its proper divisors (1366323).

3478979821 is a wasteful number, since it uses less digits than its factorization.

3478979821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1366322.

The product of its digits is 6096384, while the sum is 58.

The square root of 3478979821 is about 58982.8773543645. The cubic root of 3478979821 is about 1515.2488738541.

The spelling of 3478979821 in words is "three billion, four hundred seventy-eight million, nine hundred seventy-nine thousand, eight hundred twenty-one".