135626991 has 4 divisors (see below), whose sum is σ = 180835992. Its totient is φ = 90417992.

The previous prime is 135626989. The next prime is 135626993. The reversal of 135626991 is 199626531.

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

It is an interprime number because it is at equal distance from previous prime (135626989) and next prime (135626993).

It is a cyclic number.

It is not a de Polignac number, because 135626991 - 2¹ = 135626989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (135626993) 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, 22604496 + ... + 22604501.

It is an arithmetic number, because the mean of its divisors is an integer number (45208998).

Almost surely, 2^135626991 is an apocalyptic number.

135626991 is a deficient number, since it is larger than the sum of its proper divisors (45209001).

135626991 is an equidigital number, since it uses as much as digits as its factorization.

135626991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45209000.

The product of its digits is 87480, while the sum is 42.

The square root of 135626991 is about 11645.9001798916. The cubic root of 135626991 is about 513.7857351076.

The spelling of 135626991 in words is "one hundred thirty-five million, six hundred twenty-six thousand, nine hundred ninety-one".