21056146437 has 16 divisors (see below), whose sum is σ = 28268144640. Its totient is φ = 13940992752.

The previous prime is 21056146429. The next prime is 21056146451. The reversal of 21056146437 is 73464165012.

It is a happy number.

It is not a de Polignac number, because 21056146437 - 2³ = 21056146429 is a prime.

It is a super-2 number, since 2×21056146437² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21056146395 and 21056146404.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21056145437) 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, 397708 + ... + 447530.

It is an arithmetic number, because the mean of its divisors is an integer number (1766759040).

Almost surely, 2^21056146437 is an apocalyptic number.

It is an amenable number.

21056146437 is a deficient number, since it is larger than the sum of its proper divisors (7211998203).

21056146437 is a wasteful number, since it uses less digits than its factorization.

21056146437 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50792.

The product of its (nonzero) digits is 120960, while the sum is 39.

The spelling of 21056146437 in words is "twenty-one billion, fifty-six million, one hundred forty-six thousand, four hundred thirty-seven".