129537961 has 4 divisors (see below), whose sum is σ = 148043392. Its totient is φ = 111032532.

The previous prime is 129537931. The next prime is 129538007. The reversal of 129537961 is 169735921.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 129537961 - 2¹³ = 129529769 is a prime.

It is not an unprimeable number, because it can be changed into a prime (129537931) 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, 9252705 + ... + 9252718.

It is an arithmetic number, because the mean of its divisors is an integer number (37010848).

Almost surely, 2^129537961 is an apocalyptic number.

It is an amenable number.

129537961 is a deficient number, since it is larger than the sum of its proper divisors (18505431).

129537961 is an equidigital number, since it uses as much as digits as its factorization.

129537961 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18505430.

The product of its digits is 102060, while the sum is 43.

The square root of 129537961 is about 11381.4744651122. The cubic root of 129537961 is about 505.9788367262.

The spelling of 129537961 in words is "one hundred twenty-nine million, five hundred thirty-seven thousand, nine hundred sixty-one".