21661054461502 has 8 divisors (see below), whose sum is σ = 34402851203616. Its totient is φ = 10193437393632.

The previous prime is 21661054461443. The next prime is 21661054461559. The reversal of 21661054461502 is 20516445016612.

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

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 318544918518 + ... + 318544918585.

It is an arithmetic number, because the mean of its divisors is an integer number (4300356400452).

Almost surely, 2^{21661054461502} is an apocalyptic number.

21661054461502 is a deficient number, since it is larger than the sum of its proper divisors (12741796742114).

21661054461502 is a wasteful number, since it uses less digits than its factorization.

21661054461502 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 637089837122.

The product of its (nonzero) digits is 345600, while the sum is 43.

The spelling of 21661054461502 in words is "twenty-one trillion, six hundred sixty-one billion, fifty-four million, four hundred sixty-one thousand, five hundred two".