123701991 has 16 divisors (see below), whose sum is σ = 188937984. Its totient is φ = 70521984.

The previous prime is 123701983. The next prime is 123702001. The reversal of 123701991 is 199107321.

It is not a de Polignac number, because 123701991 - 2³ = 123701983 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (123701971) 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, 2655 + ... + 15951.

It is an arithmetic number, because the mean of its divisors is an integer number (11808624).

Almost surely, 2^123701991 is an apocalyptic number.

123701991 is a deficient number, since it is larger than the sum of its proper divisors (65235993).

123701991 is a wasteful number, since it uses less digits than its factorization.

123701991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13750.

The product of its (nonzero) digits is 3402, while the sum is 33.

The square root of 123701991 is about 11122.1396772384. The cubic root of 123701991 is about 498.2632960362.

The spelling of 123701991 in words is "one hundred twenty-three million, seven hundred one thousand, nine hundred ninety-one".