21061417402 has 16 divisors (see below), whose sum is σ = 34081630632. Its totient is φ = 9724249600.

The previous prime is 21061417393. The next prime is 21061417409. The reversal of 21061417402 is 20471416012.

It can be written as a sum of positive squares in 4 ways, for example, as 20990504161 + 70913241 = 144881^2 + 8421^2 .

It is not an unprimeable number, because it can be changed into a prime (21061417409) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5842099 + ... + 5845702.

Almost surely, 2^21061417402 is an apocalyptic number.

21061417402 is a deficient number, since it is larger than the sum of its proper divisors (13020213230).

21061417402 is a wasteful number, since it uses less digits than its factorization.

21061417402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11687873.

The product of its (nonzero) digits is 2688, while the sum is 28.

The spelling of 21061417402 in words is "twenty-one billion, sixty-one million, four hundred seventeen thousand, four hundred two".