21850570381 has 16 divisors (see below), whose sum is σ = 22689709056. Its totient is φ = 21027600000.

The previous prime is 21850570369. The next prime is 21850570393. The reversal of 21850570381 is 18307505812.

It is an interprime number because it is at equal distance from previous prime (21850570369) and next prime (21850570393).

It is a cyclic number.

It is not a de Polignac number, because 21850570381 - 2⁷ = 21850570253 is a prime.

It is a super-2 number, since 2×21850570381² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21850570321) 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, 1112476 + ... + 1131946.

It is an arithmetic number, because the mean of its divisors is an integer number (1418106816).

Almost surely, 2^21850570381 is an apocalyptic number.

It is an amenable number.

21850570381 is a deficient number, since it is larger than the sum of its proper divisors (839138675).

21850570381 is a wasteful number, since it uses less digits than its factorization.

21850570381 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19884.

The product of its (nonzero) digits is 67200, while the sum is 40.

The spelling of 21850570381 in words is "twenty-one billion, eight hundred fifty million, five hundred seventy thousand, three hundred eighty-one".