122447991 has 16 divisors (see below), whose sum is σ = 174956544. Its totient is φ = 75901824.

The previous prime is 122447981. The next prime is 122448013. The reversal of 122447991 is 199744221.

It is not a de Polignac number, because 122447991 - 2¹¹ = 122445943 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (122447921) 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, 10231 + ... + 18696.

It is an arithmetic number, because the mean of its divisors is an integer number (10934784).

Almost surely, 2^122447991 is an apocalyptic number.

122447991 is a deficient number, since it is larger than the sum of its proper divisors (52508553).

122447991 is a wasteful number, since it uses less digits than its factorization.

122447991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29030.

The product of its digits is 36288, while the sum is 39.

The square root of 122447991 is about 11065.6220340295. The cubic root of 122447991 is about 496.5738986135.

The spelling of 122447991 in words is "one hundred twenty-two million, four hundred forty-seven thousand, nine hundred ninety-one".