20201507865 has 64 divisors (see below), whose sum is σ = 44775659520. Its totient is φ = 8395427520.

The previous prime is 20201507861. The next prime is 20201507869. The reversal of 20201507865 is 56870510202.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (20201507861) and next prime (20201507869).

It is not a de Polignac number, because 20201507865 - 2² = 20201507861 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20201507861) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 961299 + ... + 982088.

It is an arithmetic number, because the mean of its divisors is an integer number (699619680).

Almost surely, 2^20201507865 is an apocalyptic number.

It is an amenable number.

20201507865 is an abundant number, since it is smaller than the sum of its proper divisors (24574151655).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20201507865 is a wasteful number, since it uses less digits than its factorization.

20201507865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1943419 (or 1943413 counting only the distinct ones).

The product of its (nonzero) digits is 33600, while the sum is 36.

The spelling of 20201507865 in words is "twenty billion, two hundred one million, five hundred seven thousand, eight hundred sixty-five".