21263626990 has 16 divisors (see below), whose sum is σ = 38474922240. Its totient is φ = 8460918880.

The previous prime is 21263626987. The next prime is 21263627027. The reversal of 21263626990 is 9962636212.

It is a self number, because there is not a number n which added to its sum of digits gives 21263626990.

It is a congruent number.

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, 5564485 + ... + 5568304.

It is an arithmetic number, because the mean of its divisors is an integer number (2404682640).

Almost surely, 2^21263626990 is an apocalyptic number.

21263626990 is a deficient number, since it is larger than the sum of its proper divisors (17211295250).

21263626990 is a wasteful number, since it uses less digits than its factorization.

21263626990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11132987.

The product of its (nonzero) digits is 419904, while the sum is 46.

The spelling of 21263626990 in words is "twenty-one billion, two hundred sixty-three million, six hundred twenty-six thousand, nine hundred ninety".