139809787 has 4 divisors (see below), whose sum is σ = 150564400. Its totient is φ = 129055176.

The previous prime is 139809773. The next prime is 139809797. The reversal of 139809787 is 787908931.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 787908931 = 41 ⋅19217291.

It is a cyclic number.

It is not a de Polignac number, because 139809787 - 2¹¹ = 139807739 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (139809757) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 5377287 + ... + 5377312.

It is an arithmetic number, because the mean of its divisors is an integer number (37641100).

Almost surely, 2^139809787 is an apocalyptic number.

139809787 is a deficient number, since it is larger than the sum of its proper divisors (10754613).

139809787 is a wasteful number, since it uses less digits than its factorization.

139809787 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10754612.

The product of its (nonzero) digits is 762048, while the sum is 52.

The square root of 139809787 is about 11824.1188678058. The cubic root of 139809787 is about 519.0141417263.

The spelling of 139809787 in words is "one hundred thirty-nine million, eight hundred nine thousand, seven hundred eighty-seven".