40215021 has 16 divisors (see below), whose sum is σ = 66851328. Its totient is φ = 20890800.

The previous prime is 40214983. The next prime is 40215023. The reversal of 40215021 is 12051204.

It is not a de Polignac number, because 40215021 - 2⁶ = 40214957 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40215023) 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, 86815 + ... + 87276.

It is an arithmetic number, because the mean of its divisors is an integer number (4178208).

Almost surely, 2^40215021 is an apocalyptic number.

It is an amenable number.

40215021 is a deficient number, since it is larger than the sum of its proper divisors (26636307).

40215021 is a wasteful number, since it uses less digits than its factorization.

40215021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174112.

The product of its (nonzero) digits is 80, while the sum is 15.

The square root of 40215021 is about 6341.5314396445. The cubic root of 40215021 is about 342.6068957901.

Adding to 40215021 its reverse (12051204), we get a palindrome (52266225).

The spelling of 40215021 in words is "forty million, two hundred fifteen thousand, twenty-one".