20121270 has 32 divisors (see below), whose sum is σ = 52006752. Its totient is φ = 4952832.

The previous prime is 20121193. The next prime is 20121271. The reversal of 20121270 is 7212102.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20121271) 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, 25407 + ... + 26186.

It is an arithmetic number, because the mean of its divisors is an integer number (1625211).

Almost surely, 2^20121270 is an apocalyptic number.

20121270 is an abundant number, since it is smaller than the sum of its proper divisors (31885482).

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

20121270 is a wasteful number, since it uses less digits than its factorization.

20121270 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51616.

The product of its (nonzero) digits is 56, while the sum is 15.

The square root of 20121270 is about 4485.6738624202. The cubic root of 20121270 is about 271.9892855497.

Adding to 20121270 its reverse (7212102), we get a palindrome (27333372).

The spelling of 20121270 in words is "twenty million, one hundred twenty-one thousand, two hundred seventy".