21355073045 has 6 divisors (see below), whose sum is σ = 25626479778. Its totient is φ = 17083797024.

The previous prime is 21355073023. The next prime is 21355073053. The reversal of 21355073045 is 54037055312.

It can be written as a sum of positive squares in 3 ways, for example, as 10330283044 + 11024790001 = 101638^2 + 104999^2 .

It is not a de Polignac number, because 21355073045 - 2²² = 21350878741 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21355072996 and 21355073014.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 294089 + ... + 359441.

It is an arithmetic number, because the mean of its divisors is an integer number (4271079963).

Almost surely, 2^21355073045 is an apocalyptic number.

It is an amenable number.

21355073045 is a deficient number, since it is larger than the sum of its proper divisors (4271406733).

21355073045 is an frugal number, since it uses more digits than its factorization.

21355073045 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 130711 (or 65358 counting only the distinct ones).

The product of its (nonzero) digits is 63000, while the sum is 35.

The spelling of 21355073045 in words is "twenty-one billion, three hundred fifty-five million, seventy-three thousand, forty-five".