101139491 has 2 divisors, whose sum is σ = 101139492. Its totient is φ = 101139490.

The previous prime is 101139461. The next prime is 101139499. The reversal of 101139491 is 194931101.

It is a strong prime.

It is an emirp because it is prime and its reverse (194931101) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 101139491 - 2¹⁰ = 101138467 is a prime.

It is a Sophie Germain prime.

It is not a weakly prime, because it can be changed into another prime (101139499) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 50569745 + 50569746.

It is an arithmetic number, because the mean of its divisors is an integer number (50569746).

Almost surely, 2^101139491 is an apocalyptic number.

101139491 is a deficient number, since it is larger than the sum of its proper divisors (1).

101139491 is an equidigital number, since it uses as much as digits as its factorization.

101139491 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 972, while the sum is 29.

The square root of 101139491 is about 10056.8131632242. The cubic root of 101139491 is about 465.9152451974.

The spelling of 101139491 in words is "one hundred one million, one hundred thirty-nine thousand, four hundred ninety-one".