72428139 has 24 divisors (see below), whose sum is σ = 121355520. Its totient is φ = 40767408.

The previous prime is 72428131. The next prime is 72428149. The reversal of 72428139 is 93182427.

It is not a de Polignac number, because 72428139 - 2³ = 72428131 is a prime.

It is not an unprimeable number, because it can be changed into a prime (72428131) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 4359 + ... + 12800.

It is an arithmetic number, because the mean of its divisors is an integer number (5056480).

Almost surely, 2^72428139 is an apocalyptic number.

72428139 is a deficient number, since it is larger than the sum of its proper divisors (48927381).

72428139 is a wasteful number, since it uses less digits than its factorization.

72428139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17239 (or 17236 counting only the distinct ones).

The product of its digits is 24192, while the sum is 36.

The square root of 72428139 is about 8510.4723135676. The cubic root of 72428139 is about 416.8397327633.

The spelling of 72428139 in words is "seventy-two million, four hundred twenty-eight thousand, one hundred thirty-nine".