21148396990 has 64 divisors (see below), whose sum is σ = 43967121408. Its totient is φ = 7174080000.

The previous prime is 21148396981. The next prime is 21148397009. The reversal of 21148396990 is 9969384112.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 8994315 + ... + 8996665.

It is an arithmetic number, because the mean of its divisors is an integer number (686986272).

Almost surely, 2^21148396990 is an apocalyptic number.

21148396990 is an abundant number, since it is smaller than the sum of its proper divisors (22818724418).

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

21148396990 is a wasteful number, since it uses less digits than its factorization.

21148396990 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3673.

The product of its (nonzero) digits is 839808, while the sum is 52.

The spelling of 21148396990 in words is "twenty-one billion, one hundred forty-eight million, three hundred ninety-six thousand, nine hundred ninety".