42213681 has 6 divisors (see below), whose sum is σ = 60975330. Its totient is φ = 28142448.

The previous prime is 42213643. The next prime is 42213683. The reversal of 42213681 is 18631224.

It can be written as a sum of positive squares in only one way, i.e., 27468081 + 14745600 = 5241^2 + 3840^2 .

It is not a de Polignac number, because 42213681 - 2⁷ = 42213553 is a prime.

It is a super-2 number, since 2×42213681² = 3563989727139522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (42213683) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2345196 + ... + 2345213.

It is an arithmetic number, because the mean of its divisors is an integer number (10162555).

Almost surely, 2^42213681 is an apocalyptic number.

It is an amenable number.

42213681 is a deficient number, since it is larger than the sum of its proper divisors (18761649).

42213681 is a wasteful number, since it uses less digits than its factorization.

42213681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4690415 (or 4690412 counting only the distinct ones).

The product of its digits is 2304, while the sum is 27.

The square root of 42213681 is about 6497.2056301151. The cubic root of 42213681 is about 348.1911603329.

The spelling of 42213681 in words is "forty-two million, two hundred thirteen thousand, six hundred eighty-one".