1020400240123 has 4 divisors (see below), whose sum is σ = 1113163898328. Its totient is φ = 927636581920.

The previous prime is 1020400240109. The next prime is 1020400240157. The reversal of 1020400240123 is 3210420040201.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1020400240123 - 2¹³ = 1020400231931 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1020400240123.

It is not an unprimeable number, because it can be changed into a prime (1020400240103) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 46381829086 + ... + 46381829107.

It is an arithmetic number, because the mean of its divisors is an integer number (278290974582).

Almost surely, 2^{1020400240123} is an apocalyptic number.

1020400240123 is a deficient number, since it is larger than the sum of its proper divisors (92763658205).

1020400240123 is an equidigital number, since it uses as much as digits as its factorization.

1020400240123 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92763658204.

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 1020400240123 its reverse (3210420040201), we get a palindrome (4230820280324).

The spelling of 1020400240123 in words is "one trillion, twenty billion, four hundred million, two hundred forty thousand, one hundred twenty-three".