21961607902 has 16 divisors (see below), whose sum is σ = 35564930352. Its totient is φ = 10110844800.

The previous prime is 21961607887. The next prime is 21961607911. The reversal of 21961607902 is 20970616912.

It is a happy number.

It is a super-3 number, since 3×21961607902³ (a number of 32 digits) contains 333 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1042788 + ... + 1063639.

It is an arithmetic number, because the mean of its divisors is an integer number (2222808147).

Almost surely, 2^21961607902 is an apocalyptic number.

21961607902 is a deficient number, since it is larger than the sum of its proper divisors (13603322450).

21961607902 is a wasteful number, since it uses less digits than its factorization.

21961607902 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2106843.

The product of its (nonzero) digits is 81648, while the sum is 43.

The spelling of 21961607902 in words is "twenty-one billion, nine hundred sixty-one million, six hundred seven thousand, nine hundred two".