31423155 has 16 divisors (see below), whose sum is σ = 50380704. Its totient is φ = 16724480.

The previous prime is 31423127. The next prime is 31423159. The reversal of 31423155 is 55132413.

It is not a de Polignac number, because 31423155 - 2¹¹ = 31421107 is a prime.

It is not an unprimeable number, because it can be changed into a prime (31423159) 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, 6475 + ... + 10235.

It is an arithmetic number, because the mean of its divisors is an integer number (3148794).

Almost surely, 2^31423155 is an apocalyptic number.

31423155 is a deficient number, since it is larger than the sum of its proper divisors (18957549).

31423155 is a wasteful number, since it uses less digits than its factorization.

31423155 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4326.

The product of its digits is 1800, while the sum is 24.

The square root of 31423155 is about 5605.6360031668. The cubic root of 31423155 is about 315.5609556033.

Adding to 31423155 its reverse (55132413), we get a palindrome (86555568).

The spelling of 31423155 in words is "thirty-one million, four hundred twenty-three thousand, one hundred fifty-five".