40207421 has 4 divisors (see below), whose sum is σ = 40448352. Its totient is φ = 39966492.

The previous prime is 40207417. The next prime is 40207423. The reversal of 40207421 is 12470204.

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 40207421 - 2² = 40207417 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 40207393 and 40207402.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (40207423) 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, 120215 + ... + 120548.

It is an arithmetic number, because the mean of its divisors is an integer number (10112088).

Almost surely, 2^40207421 is an apocalyptic number.

It is an amenable number.

40207421 is a deficient number, since it is larger than the sum of its proper divisors (240931).

40207421 is a wasteful number, since it uses less digits than its factorization.

40207421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 240930.

The product of its (nonzero) digits is 448, while the sum is 20.

The square root of 40207421 is about 6340.9321869895. The cubic root of 40207421 is about 342.5853120105.

Adding to 40207421 its reverse (12470204), we get a palindrome (52677625).

The spelling of 40207421 in words is "forty million, two hundred seven thousand, four hundred twenty-one".