213617421 has 24 divisors (see below), whose sum is σ = 323459136. Its totient is φ = 135696960.

The previous prime is 213617419. The next prime is 213617423. The reversal of 213617421 is 124716312.

213617421 is a `hidden beast` number, since 2 + 1 + 3 + 617 + 42 + 1 = 666.

It is an interprime number because it is at equal distance from previous prime (213617419) and next prime (213617423).

It is not a de Polignac number, because 213617421 - 2¹ = 213617419 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (213617423) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9136 + ... + 22598.

It is an arithmetic number, because the mean of its divisors is an integer number (13477464).

Almost surely, 2^213617421 is an apocalyptic number.

It is an amenable number.

213617421 is a deficient number, since it is larger than the sum of its proper divisors (109841715).

213617421 is a wasteful number, since it uses less digits than its factorization.

213617421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13553 (or 13550 counting only the distinct ones).

The product of its digits is 2016, while the sum is 27.

The square root of 213617421 is about 14615.6567077911. The cubic root of 213617421 is about 597.7857468572.

It can be divided in two parts, 21361 and 7421, that added together give a palindrome (28782).

The spelling of 213617421 in words is "two hundred thirteen million, six hundred seventeen thousand, four hundred twenty-one".