128722407 has 8 divisors (see below), whose sum is σ = 187232640. Its totient is φ = 78013560.

The previous prime is 128722403. The next prime is 128722409. The reversal of 128722407 is 704227821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 128722407 - 2² = 128722403 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (33), and also a Moran number because the ratio is a prime number: 3900679 = 128722407 / (1 + 2 + 8 + 7 + 2 + 2 + 4 + 0 + 7).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (128722403) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1950307 + ... + 1950372.

It is an arithmetic number, because the mean of its divisors is an integer number (23404080).

Almost surely, 2^128722407 is an apocalyptic number.

128722407 is a deficient number, since it is larger than the sum of its proper divisors (58510233).

128722407 is a wasteful number, since it uses less digits than its factorization.

128722407 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3900693.

The product of its (nonzero) digits is 12544, while the sum is 33.

The square root of 128722407 is about 11345.5897599023. The cubic root of 128722407 is about 504.9147416765.

The spelling of 128722407 in words is "one hundred twenty-eight million, seven hundred twenty-two thousand, four hundred seven".