21009163061 has 8 divisors (see below), whose sum is σ = 21209451480. Its totient is φ = 20809126912.

The previous prime is 21009163027. The next prime is 21009163081. The reversal of 21009163061 is 16036190012.

It can be written as a sum of positive squares in 4 ways, for example, as 6676524100 + 14332638961 = 81710^2 + 119719^2 .

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21009163061 is a prime.

It is a super-3 number, since 3×21009163061³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21009163001) 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, 106445 + ... + 230973.

It is an arithmetic number, because the mean of its divisors is an integer number (2651181435).

Almost surely, 2^21009163061 is an apocalyptic number.

It is an amenable number.

21009163061 is a deficient number, since it is larger than the sum of its proper divisors (200288419).

21009163061 is a wasteful number, since it uses less digits than its factorization.

21009163061 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 126135.

The product of its (nonzero) digits is 1944, while the sum is 29.

The spelling of 21009163061 in words is "twenty-one billion, nine million, one hundred sixty-three thousand, sixty-one".