21070386 has 24 divisors (see below), whose sum is σ = 46298304. Its totient is φ = 6924120.

The previous prime is 21070363. The next prime is 21070393. The reversal of 21070386 is 68307012.

21070386 is a `hidden beast` number, since 210 + 70 + 386 = 666.

It is a super-2 number, since 2×21070386² = 887922332377992, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6966 + ... + 9521.

It is an arithmetic number, because the mean of its divisors is an integer number (1929096).

Almost surely, 2^21070386 is an apocalyptic number.

21070386 is an abundant number, since it is smaller than the sum of its proper divisors (25227918).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21070386 is a wasteful number, since it uses less digits than its factorization.

21070386 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16566 (or 16563 counting only the distinct ones).

The product of its (nonzero) digits is 2016, while the sum is 27.

The square root of 21070386 is about 4590.2490128532. The cubic root of 21070386 is about 276.2003114224.

Adding to 21070386 its reverse (68307012), we get a palindrome (89377398).

The spelling of 21070386 in words is "twenty-one million, seventy thousand, three hundred eighty-six".