20115501 has 16 divisors (see below), whose sum is σ = 31985664. Its totient is φ = 10994544.

The previous prime is 20115493. The next prime is 20115503. The reversal of 20115501 is 10551102.

It is not a de Polignac number, because 20115501 - 2³ = 20115493 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20115503) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 20341 + ... + 21306.

It is an arithmetic number, because the mean of its divisors is an integer number (1999104).

Almost surely, 2^20115501 is an apocalyptic number.

20115501 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20115501 is a deficient number, since it is larger than the sum of its proper divisors (11870163).

20115501 is a wasteful number, since it uses less digits than its factorization.

20115501 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41680.

The product of its (nonzero) digits is 50, while the sum is 15.

The square root of 20115501 is about 4485.0307691252. The cubic root of 20115501 is about 271.9632889108.

Adding to 20115501 its reverse (10551102), we get a palindrome (30666603).

The spelling of 20115501 in words is "twenty million, one hundred fifteen thousand, five hundred one".