1021000012123 has 16 divisors (see below), whose sum is σ = 1258652122560. Its totient is φ = 806514863616.

The previous prime is 1021000012099. The next prime is 1021000012141. The reversal of 1021000012123 is 3212100001201.

It is not a de Polignac number, because 1021000012123 - 2¹⁷ = 1020999881051 is a prime.

It is a super-2 number, since 2×1021000012123² (a number of 25 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (13).

It is not an unprimeable number, because it can be changed into a prime (1021000012163) 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, 9036058 + ... + 9148351.

It is an arithmetic number, because the mean of its divisors is an integer number (78665757660).

Almost surely, 2^{1021000012123} is an apocalyptic number.

1021000012123 is a gapful number since it is divisible by the number (13) formed by its first and last digit.

1021000012123 is a deficient number, since it is larger than the sum of its proper divisors (237652110437).

1021000012123 is a wasteful number, since it uses less digits than its factorization.

1021000012123 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18185046.

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 1021000012123 its reverse (3212100001201), we get a palindrome (4233100013324).

The spelling of 1021000012123 in words is "one trillion, twenty-one billion, twelve thousand, one hundred twenty-three".