101221099978 has 8 divisors (see below), whose sum is σ = 153305743968. Its totient is φ = 50119185324.

The previous prime is 101221099961. The next prime is 101221099999. The reversal of 101221099978 is 879990122101.

It is a happy number.

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

It is a super-2 number, since 2×101221099978² (a number of 23 digits) contains 22 as substring.

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, 245682076 + ... + 245682487.

It is an arithmetic number, because the mean of its divisors is an integer number (19163217996).

Almost surely, 2^101221099978 is an apocalyptic number.

101221099978 is a deficient number, since it is larger than the sum of its proper divisors (52084643990).

101221099978 is a wasteful number, since it uses less digits than its factorization.

101221099978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 491364668.

The product of its (nonzero) digits is 163296, while the sum is 49.

The spelling of 101221099978 in words is "one hundred one billion, two hundred twenty-one million, ninety-nine thousand, nine hundred seventy-eight".