21061103570 has 32 divisors (see below), whose sum is σ = 40865921712. Its totient is φ = 7768829952.

The previous prime is 21061103561. The next prime is 21061103587. The reversal of 21061103570 is 7530116012.

It can be written as a sum of positive squares in 8 ways, for example, as 7878160081 + 13182943489 = 88759^2 + 114817^2 .

It is a Harshad number since it is a multiple of its sum of digits (26).

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 55874 + ... + 212706.

Almost surely, 2^21061103570 is an apocalyptic number.

21061103570 is a deficient number, since it is larger than the sum of its proper divisors (19804818142).

21061103570 is a wasteful number, since it uses less digits than its factorization.

21061103570 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 157886.

The product of its (nonzero) digits is 1260, while the sum is 26.

Adding to 21061103570 its reverse (7530116012), we get a palindrome (28591219582).

The spelling of 21061103570 in words is "twenty-one billion, sixty-one million, one hundred three thousand, five hundred seventy".