231220407 has 8 divisors (see below), whose sum is σ = 336320640. Its totient is φ = 140133560.

The previous prime is 231220387. The next prime is 231220421. The reversal of 231220407 is 704022132.

231220407 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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 231220407 - 2¹⁰ = 231219383 is a prime.

It is a super-2 number, since 2×231220407² = 106925753226491298, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (231220907) 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, 3503307 + ... + 3503372.

It is an arithmetic number, because the mean of its divisors is an integer number (42040080).

Almost surely, 2^231220407 is an apocalyptic number.

231220407 is a deficient number, since it is larger than the sum of its proper divisors (105100233).

231220407 is a wasteful number, since it uses less digits than its factorization.

231220407 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7006693.

The product of its (nonzero) digits is 672, while the sum is 21.

The square root of 231220407 is about 15205.9332827683. The cubic root of 231220407 is about 613.7743293505.

Adding to 231220407 its reverse (704022132), we get a palindrome (935242539).

The spelling of 231220407 in words is "two hundred thirty-one million, two hundred twenty thousand, four hundred seven".