40642421 has 2 divisors, whose sum is σ = 40642422. Its totient is φ = 40642420.

The previous prime is 40642417. The next prime is 40642447. The reversal of 40642421 is 12424604.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 33292900 + 7349521 = 5770^2 + 2711^2 .

It is a cyclic number.

It is not a de Polignac number, because 40642421 - 2² = 40642417 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (40642411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 20321210 + 20321211.

It is an arithmetic number, because the mean of its divisors is an integer number (20321211).

Almost surely, 2^40642421 is an apocalyptic number.

It is an amenable number.

40642421 is a deficient number, since it is larger than the sum of its proper divisors (1).

40642421 is an equidigital number, since it uses as much as digits as its factorization.

40642421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1536, while the sum is 23.

The square root of 40642421 is about 6375.1408611889. The cubic root of 40642421 is about 343.8163483611.

The spelling of 40642421 in words is "forty million, six hundred forty-two thousand, four hundred twenty-one".