400023621 has 12 divisors (see below), whose sum is σ = 580232640. Its totient is φ = 265565160.

The previous prime is 400023607. The next prime is 400023623. The reversal of 400023621 is 126320004.

It is a happy number.

400023621 is a `hidden beast` number, since 40 + 0 + 0 + 2 + 3 + 621 = 666.

It is not a de Polignac number, because 400023621 - 2⁶ = 400023557 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 400023594 and 400023603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400023623) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 90835 + ... + 95136.

It is an arithmetic number, because the mean of its divisors is an integer number (48352720).

Almost surely, 2^400023621 is an apocalyptic number.

It is an amenable number.

400023621 is a deficient number, since it is larger than the sum of its proper divisors (180209019).

400023621 is a wasteful number, since it uses less digits than its factorization.

400023621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 186216 (or 186213 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 400023621 is about 20000.5905162823. The cubic root of 400023621 is about 736.8208028606.

Adding to 400023621 its reverse (126320004), we get a palindrome (526343625).

The spelling of 400023621 in words is "four hundred million, twenty-three thousand, six hundred twenty-one".