201311012123 has 64 divisors (see below), whose sum is σ = 232937413632. Its totient is φ = 172574392320.

The previous prime is 201311012069. The next prime is 201311012143. The reversal of 201311012123 is 321210113102.

It is a cyclic number.

It is not a de Polignac number, because 201311012123 - 2¹² = 201311008027 is a prime.

It is a super-2 number, since 2×201311012123² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (201311012143) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 580146836 + ... + 580147182.

It is an arithmetic number, because the mean of its divisors is an integer number (3639647088).

Almost surely, 2^201311012123 is an apocalyptic number.

201311012123 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

201311012123 is a deficient number, since it is larger than the sum of its proper divisors (31626401509).

201311012123 is a wasteful number, since it uses less digits than its factorization.

201311012123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 804.

The product of its (nonzero) digits is 72, while the sum is 17.

Adding to 201311012123 its reverse (321210113102), we get a palindrome (522521125225).

The spelling of 201311012123 in words is "two hundred one billion, three hundred eleven million, twelve thousand, one hundred twenty-three".