21001430155535 has 8 divisors (see below), whose sum is σ = 25451238129696. Its totient is φ = 16634796162400.

The previous prime is 21001430155523. The next prime is 21001430155583. The reversal of 21001430155535 is 53555103410012.

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

It is not a de Polignac number, because 21001430155535 - 2⁶ = 21001430155471 is a prime.

It is a super-2 number, since 2×21001430155535² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21001430155495 and 21001430155504.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 20793494699 + ... + 20793495708.

It is an arithmetic number, because the mean of its divisors is an integer number (3181404766212).

Almost surely, 2^{21001430155535} is an apocalyptic number.

21001430155535 is a deficient number, since it is larger than the sum of its proper divisors (4449807974161).

21001430155535 is a wasteful number, since it uses less digits than its factorization.

21001430155535 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 41586990513.

The product of its (nonzero) digits is 45000, while the sum is 35.

Adding to 21001430155535 its reverse (53555103410012), we get a palindrome (74556533565547).

The spelling of 21001430155535 in words is "twenty-one trillion, one billion, four hundred thirty million, one hundred fifty-five thousand, five hundred thirty-five".