40102021 has 4 divisors (see below), whose sum is σ = 40117792. Its totient is φ = 40086252.

The previous prime is 40102001. The next prime is 40102033. The reversal of 40102021 is 12020104.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 40102021 - 2¹¹ = 40099973 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 40101989 and 40102007.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40102001) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3105 + ... + 9478.

It is an arithmetic number, because the mean of its divisors is an integer number (10029448).

Almost surely, 2^40102021 is an apocalyptic number.

It is an amenable number.

40102021 is a deficient number, since it is larger than the sum of its proper divisors (15771).

40102021 is a wasteful number, since it uses less digits than its factorization.

40102021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15770.

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 40102021 is about 6332.6156523193. The cubic root of 40102021 is about 342.2856982518.

Adding to 40102021 its reverse (12020104), we get a palindrome (52122125).

The spelling of 40102021 in words is "forty million, one hundred two thousand, twenty-one".