53399987 has 4 divisors (see below), whose sum is σ = 53495400. Its totient is φ = 53304576.

The previous prime is 53399981. The next prime is 53400001. The reversal of 53399987 is 78999335.

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

It is a cyclic number.

It is not a de Polignac number, because 53399987 - 2¹² = 53395891 is a prime.

It is a super-2 number, since 2×53399987² = 5703117223200338, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (53399981) 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, 46862 + ... + 47987.

It is an arithmetic number, because the mean of its divisors is an integer number (13373850).

Almost surely, 2^53399987 is an apocalyptic number.

53399987 is a deficient number, since it is larger than the sum of its proper divisors (95413).

53399987 is an equidigital number, since it uses as much as digits as its factorization.

53399987 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 95412.

The product of its digits is 1837080, while the sum is 53.

The square root of 53399987 is about 7307.5294730846. The cubic root of 53399987 is about 376.5711550280.

The spelling of 53399987 in words is "fifty-three million, three hundred ninety-nine thousand, nine hundred eighty-seven".