221297408642 has 30 divisors (see below), whose sum is σ = 352999185519. Its totient is φ = 104049479200.

The previous prime is 221297408639. The next prime is 221297408653. The reversal of 221297408642 is 246804792122.

It can be written as a sum of positive squares in 3 ways, for example, as 213029325601 + 8268083041 = 461551^2 + 90929^2 .

It is an ABA number since it can be written as A⋅B^A, here for A=2, B=332639.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 14 ways as a sum of consecutive naturals, for example, 192264767 + ... + 192265917.

Almost surely, 2^221297408642 is an apocalyptic number.

221297408642 is a deficient number, since it is larger than the sum of its proper divisors (131701776877).

221297408642 is an frugal number, since it uses more digits than its factorization.

221297408642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2372 (or 1170 counting only the distinct ones).

The product of its (nonzero) digits is 774144, while the sum is 47.

The spelling of 221297408642 in words is "two hundred twenty-one billion, two hundred ninety-seven million, four hundred eight thousand, six hundred forty-two".