21135035402 has 8 divisors (see below), whose sum is σ = 34141211076. Its totient is φ = 9754631712.

The previous prime is 21135035381. The next prime is 21135035489. The reversal of 21135035402 is 20453053112.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 17027379121 + 4107656281 = 130489^2 + 64091^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a Harshad number since it is a multiple of its sum of digits (26), and also a Moran number because the ratio is a prime number: 812885977 = 21135035402 / (2 + 1 + 1 + 3 + 5 + 0 + 3 + 5 + 4 + 0 + 2).

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 406442963 + ... + 406443014.

Almost surely, 2^21135035402 is an apocalyptic number.

21135035402 is a deficient number, since it is larger than the sum of its proper divisors (13006175674).

21135035402 is a wasteful number, since it uses less digits than its factorization.

21135035402 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 812885992.

The product of its (nonzero) digits is 3600, while the sum is 26.

Adding to 21135035402 its reverse (20453053112), we get a palindrome (41588088514).

The spelling of 21135035402 in words is "twenty-one billion, one hundred thirty-five million, thirty-five thousand, four hundred two".