2171123031 has 16 divisors (see below), whose sum is σ = 3609139968. Its totient is φ = 1127856000.

The previous prime is 2171123021. The next prime is 2171123069. The reversal of 2171123031 is 1303211712.

It is a happy number.

It is not a de Polignac number, because 2171123031 - 2¹³ = 2171114839 is a prime.

It is a super-2 number, since 2×2171123031² = 9427550431477253922, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a junction number, because it is equal to n+sod(n) for n = 2171122989 and 2171123007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2171123021) 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, 4699170 + ... + 4699631.

It is an arithmetic number, because the mean of its divisors is an integer number (225571248).

Almost surely, 2^2171123031 is an apocalyptic number.

2171123031 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

2171123031 is a deficient number, since it is larger than the sum of its proper divisors (1438016937).

2171123031 is a wasteful number, since it uses less digits than its factorization.

2171123031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9398822.

The product of its (nonzero) digits is 252, while the sum is 21.

The square root of 2171123031 is about 46595.3112555330. The cubic root of 2171123031 is about 1294.8758905722.

Adding to 2171123031 its reverse (1303211712), we get a palindrome (3474334743).

The spelling of 2171123031 in words is "two billion, one hundred seventy-one million, one hundred twenty-three thousand, thirty-one".