72206421 has 16 divisors (see below), whose sum is σ = 110434944. Its totient is φ = 41108544.

The previous prime is 72206413. The next prime is 72206423. The reversal of 72206421 is 12460227.

It is not a de Polignac number, because 72206421 - 2³ = 72206413 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 72206391 and 72206400.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (72206423) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 390 + ... + 12023.

It is an arithmetic number, because the mean of its divisors is an integer number (6902184).

Almost surely, 2^72206421 is an apocalyptic number.

It is an amenable number.

72206421 is a deficient number, since it is larger than the sum of its proper divisors (38228523).

72206421 is a wasteful number, since it uses less digits than its factorization.

72206421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12700.

The product of its (nonzero) digits is 1344, while the sum is 24.

The square root of 72206421 is about 8497.4361427433. The cubic root of 72206421 is about 416.4139528545.

Adding to 72206421 its reverse (12460227), we get a palindrome (84666648).

It can be divided in two parts, 72206 and 421, that added together give a palindrome (72627).

The spelling of 72206421 in words is "seventy-two million, two hundred six thousand, four hundred twenty-one".