21022329978 has 48 divisors (see below), whose sum is σ = 50868863136. Its totient is φ = 6468407280.

The previous prime is 21022329959. The next prime is 21022329983. The reversal of 21022329978 is 87992322012.

It is a happy number.

21022329978 is a `hidden beast` number, since 210 + 22 + 329 + 97 + 8 = 666.

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 23 ways as a sum of consecutive naturals, for example, 1657368 + ... + 1670003.

It is an arithmetic number, because the mean of its divisors is an integer number (1059767982).

Almost surely, 2^21022329978 is an apocalyptic number.

21022329978 is an abundant number, since it is smaller than the sum of its proper divisors (29846533158).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21022329978 is a wasteful number, since it uses less digits than its factorization.

21022329978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3327401 (or 3327389 counting only the distinct ones).

The product of its (nonzero) digits is 217728, while the sum is 45.

The spelling of 21022329978 in words is "twenty-one billion, twenty-two million, three hundred twenty-nine thousand, nine hundred seventy-eight".