20015247 has 16 divisors (see below), whose sum is σ = 30620672. Its totient is φ = 11391840.

The previous prime is 20015231. The next prime is 20015251. The reversal of 20015247 is 74251002.

It is not a de Polignac number, because 20015247 - 2⁴ = 20015231 is a prime.

It is a super-2 number, since 2×20015247² = 801220224942018, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20015207) 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, 3933 + ... + 7449.

It is an arithmetic number, because the mean of its divisors is an integer number (1913792).

Almost surely, 2^20015247 is an apocalyptic number.

20015247 is a deficient number, since it is larger than the sum of its proper divisors (10605425).

20015247 is a wasteful number, since it uses less digits than its factorization.

20015247 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3798.

The product of its (nonzero) digits is 560, while the sum is 21.

The square root of 20015247 is about 4473.8402966579. The cubic root of 20015247 is about 271.5107220141.

Adding to 20015247 its reverse (74251002), we get a palindrome (94266249).

The spelling of 20015247 in words is "twenty million, fifteen thousand, two hundred forty-seven".