21020650424 has 8 divisors (see below), whose sum is σ = 39413719560. Its totient is φ = 10510325208.

The previous prime is 21020650423. The next prime is 21020650451. The reversal of 21020650424 is 42405602012.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×21020650424² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21020650393 and 21020650402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21020650423) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1313790644 + ... + 1313790659.

It is an arithmetic number, because the mean of its divisors is an integer number (4926714945).

Almost surely, 2^21020650424 is an apocalyptic number.

It is an amenable number.

21020650424 is a deficient number, since it is larger than the sum of its proper divisors (18393069136).

21020650424 is a wasteful number, since it uses less digits than its factorization.

21020650424 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2627581309 (or 2627581305 counting only the distinct ones).

The product of its (nonzero) digits is 3840, while the sum is 26.

The spelling of 21020650424 in words is "twenty-one billion, twenty million, six hundred fifty thousand, four hundred twenty-four".