21101553213434 has 4 divisors (see below), whose sum is σ = 31652329820154. Its totient is φ = 10550776606716.

The previous prime is 21101553213431. The next prime is 21101553213437. The reversal of 21101553213434 is 43431235510112.

It is a semiprime because it is the product of two primes.

It is an interprime number because it is at equal distance from previous prime (21101553213431) and next prime (21101553213437).

It can be written as a sum of positive squares in only one way, i.e., 16193356665409 + 4908196548025 = 4024097^2 + 2215445^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21101553213394 and 21101553213403.

It is not an unprimeable number, because it can be changed into a prime (21101553213431) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5275388303357 + ... + 5275388303360.

Almost surely, 2^{21101553213434} is an apocalyptic number.

21101553213434 is a deficient number, since it is larger than the sum of its proper divisors (10550776606720).

21101553213434 is a wasteful number, since it uses less digits than its factorization.

21101553213434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10550776606719.

The product of its (nonzero) digits is 43200, while the sum is 35.

Adding to 21101553213434 its reverse (43431235510112), we get a palindrome (64532788723546).

The spelling of 21101553213434 in words is "twenty-one trillion, one hundred one billion, five hundred fifty-three million, two hundred thirteen thousand, four hundred thirty-four".