21265026061 has 16 divisors (see below), whose sum is σ = 21898840320. Its totient is φ = 20639125440.

The previous prime is 21265026059. The next prime is 21265026067. The reversal of 21265026061 is 16062056212.

It is a cyclic number.

It is not a de Polignac number, because 21265026061 - 2¹ = 21265026059 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21265026067) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9020895 + ... + 9023251.

It is an arithmetic number, because the mean of its divisors is an integer number (1368677520).

Almost surely, 2^21265026061 is an apocalyptic number.

It is an amenable number.

21265026061 is a deficient number, since it is larger than the sum of its proper divisors (633814259).

21265026061 is a wasteful number, since it uses less digits than its factorization.

21265026061 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3924.

The product of its (nonzero) digits is 8640, while the sum is 31.

The spelling of 21265026061 in words is "twenty-one billion, two hundred sixty-five million, twenty-six thousand, sixty-one".