21122119978 has 16 divisors (see below), whose sum is σ = 32771059776. Its totient is φ = 10203435360.

The previous prime is 21122119933. The next prime is 21122119987. The reversal of 21122119978 is 87991122112.

It is a happy number.

It is a super-2 number, since 2×21122119978² (a number of 21 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1241976 + ... + 1258867.

It is an arithmetic number, because the mean of its divisors is an integer number (2048191236).

Almost surely, 2^21122119978 is an apocalyptic number.

21122119978 is a deficient number, since it is larger than the sum of its proper divisors (11648939798).

21122119978 is a wasteful number, since it uses less digits than its factorization.

21122119978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2500989.

The product of its digits is 36288, while the sum is 43.

The spelling of 21122119978 in words is "twenty-one billion, one hundred twenty-two million, one hundred nineteen thousand, nine hundred seventy-eight".