21450740673766 has 16 divisors (see below), whose sum is σ = 32317525401840. Its totient is φ = 10678234836960.

The previous prime is 21450740673707. The next prime is 21450740673767. The reversal of 21450740673766 is 66737604705412.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 21450740673766.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21450740673767) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16140561 + ... + 17418931.

It is an arithmetic number, because the mean of its divisors is an integer number (2019845337615).

Almost surely, 2^{21450740673766} is an apocalyptic number.

21450740673766 is a deficient number, since it is larger than the sum of its proper divisors (10866784728074).

21450740673766 is a wasteful number, since it uses less digits than its factorization.

21450740673766 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1315239.

The product of its (nonzero) digits is 35562240, while the sum is 58.

The spelling of 21450740673766 in words is "twenty-one trillion, four hundred fifty billion, seven hundred forty million, six hundred seventy-three thousand, seven hundred sixty-six".