139531811 has 4 divisors (see below), whose sum is σ = 139665624. Its totient is φ = 139398000.

The previous prime is 139531793. The next prime is 139531813. The reversal of 139531811 is 118135931.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 139531811 - 2⁶ = 139531747 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (139531813) 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, 65330 + ... + 67431.

It is an arithmetic number, because the mean of its divisors is an integer number (34916406).

Almost surely, 2^139531811 is an apocalyptic number.

139531811 is a deficient number, since it is larger than the sum of its proper divisors (133813).

139531811 is a wasteful number, since it uses less digits than its factorization.

139531811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133812.

The product of its digits is 3240, while the sum is 32.

The square root of 139531811 is about 11812.3584012677. The cubic root of 139531811 is about 518.6699378836.

The spelling of 139531811 in words is "one hundred thirty-nine million, five hundred thirty-one thousand, eight hundred eleven".