101997139 has 4 divisors (see below), whose sum is σ = 102040120. Its totient is φ = 101954160.

The previous prime is 101997131. The next prime is 101997151. The reversal of 101997139 is 931799101.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 931799101 = 71 ⋅13123931.

It is a cyclic number.

It is not a de Polignac number, because 101997139 - 2³ = 101997131 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (101997131) 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, 17709 + ... + 22750.

It is an arithmetic number, because the mean of its divisors is an integer number (25510030).

Almost surely, 2^101997139 is an apocalyptic number.

101997139 is a deficient number, since it is larger than the sum of its proper divisors (42981).

101997139 is an equidigital number, since it uses as much as digits as its factorization.

101997139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42980.

The product of its (nonzero) digits is 15309, while the sum is 40.

The square root of 101997139 is about 10099.3632967628. The cubic root of 101997139 is about 467.2285043200.

The spelling of 101997139 in words is "one hundred one million, nine hundred ninety-seven thousand, one hundred thirty-nine".