126123580781 has 16 divisors (see below), whose sum is σ = 151127907840. Its totient is φ = 103900428720.

The previous prime is 126123580733. The next prime is 126123580787. The reversal of 126123580781 is 187085321621.

It is not a de Polignac number, because 126123580781 - 2¹⁴ = 126123564397 is a prime.

It is a super-2 number, since 2×126123580781² (a number of 23 digits) contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (126123580787) 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, 13113935 + ... + 13123548.

It is an arithmetic number, because the mean of its divisors is an integer number (9445494240).

Almost surely, 2^126123580781 is an apocalyptic number.

126123580781 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

126123580781 is a deficient number, since it is larger than the sum of its proper divisors (25004327059).

126123580781 is a wasteful number, since it uses less digits than its factorization.

126123580781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26237536.

The product of its (nonzero) digits is 161280, while the sum is 44.

The spelling of 126123580781 in words is "one hundred twenty-six billion, one hundred twenty-three million, five hundred eighty thousand, seven hundred eighty-one".