20261570 has 32 divisors (see below), whose sum is σ = 42812928. Its totient is φ = 6758208.

The previous prime is 20261567. The next prime is 20261599. The reversal of 20261570 is 7516202.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1322 + ... + 6501.

It is an arithmetic number, because the mean of its divisors is an integer number (1337904).

Almost surely, 2^20261570 is an apocalyptic number.

20261570 is an abundant number, since it is smaller than the sum of its proper divisors (22551358).

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

20261570 is a wasteful number, since it uses less digits than its factorization.

20261570 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7874.

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 20261570 is about 4501.2853719799. The cubic root of 20261570 is about 272.6199903629.

Adding to 20261570 its reverse (7516202), we get a palindrome (27777772).

The spelling of 20261570 in words is "twenty million, two hundred sixty-one thousand, five hundred seventy".