21953963490 has 32 divisors (see below), whose sum is σ = 52899448896. Its totient is φ = 5831064000.

The previous prime is 21953963461. The next prime is 21953963491. The reversal of 21953963490 is 9436935912.

It is not an unprimeable number, because it can be changed into a prime (21953963491) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1450237 + ... + 1465296.

It is an arithmetic number, because the mean of its divisors is an integer number (1653107778).

Almost surely, 2^21953963490 is an apocalyptic number.

21953963490 is an abundant number, since it is smaller than the sum of its proper divisors (30945485406).

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

21953963490 is a wasteful number, since it uses less digits than its factorization.

21953963490 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2915794.

The product of its (nonzero) digits is 1574640, while the sum is 51.

The spelling of 21953963490 in words is "twenty-one billion, nine hundred fifty-three million, nine hundred sixty-three thousand, four hundred ninety".