21436520061 has 8 divisors (see below), whose sum is σ = 31180392864. Its totient is φ = 12991830320.

The previous prime is 21436520041. The next prime is 21436520071. The reversal of 21436520061 is 16002563412.

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

It is a cyclic number.

It is not a de Polignac number, because 21436520061 - 2⁵ = 21436520029 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21436520041) 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, 324795726 + ... + 324795791.

It is an arithmetic number, because the mean of its divisors is an integer number (3897549108).

Almost surely, 2^21436520061 is an apocalyptic number.

It is an amenable number.

21436520061 is a deficient number, since it is larger than the sum of its proper divisors (9743872803).

21436520061 is a wasteful number, since it uses less digits than its factorization.

21436520061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 649591531.

The product of its (nonzero) digits is 8640, while the sum is 30.

The spelling of 21436520061 in words is "twenty-one billion, four hundred thirty-six million, five hundred twenty thousand, sixty-one".