20135987 has 2 divisors, whose sum is σ = 20135988. Its totient is φ = 20135986.

The previous prime is 20135981. The next prime is 20135993. The reversal of 20135987 is 78953102.

It is a balanced prime because it is at equal distance from previous prime (20135981) and next prime (20135993).

It is a cyclic number.

It is not a de Polignac number, because 20135987 - 2⁶ = 20135923 is a prime.

It is not a weakly prime, because it can be changed into another prime (20135981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10067993 + 10067994.

It is an arithmetic number, because the mean of its divisors is an integer number (10067994).

Almost surely, 2^20135987 is an apocalyptic number.

20135987 is a deficient number, since it is larger than the sum of its proper divisors (1).

20135987 is an equidigital number, since it uses as much as digits as its factorization.

20135987 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 15120, while the sum is 35.

The square root of 20135987 is about 4487.3140072877. The cubic root of 20135987 is about 272.0555817426.

It can be divided in two parts, 2013 and 5987, that added together give a cube (8000 = 20³).

The spelling of 20135987 in words is "twenty million, one hundred thirty-five thousand, nine hundred eighty-seven".