400276821 has 16 divisors (see below), whose sum is σ = 630979200. Its totient is φ = 220842048.

The previous prime is 400276813. The next prime is 400276823. The reversal of 400276821 is 128672004.

It is not a de Polignac number, because 400276821 - 2³ = 400276813 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (400276823) 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, 328026 + ... + 329243.

It is an arithmetic number, because the mean of its divisors is an integer number (39436200).

Almost surely, 2^400276821 is an apocalyptic number.

It is an amenable number.

400276821 is a deficient number, since it is larger than the sum of its proper divisors (230702379).

400276821 is a wasteful number, since it uses less digits than its factorization.

400276821 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 657308.

The product of its (nonzero) digits is 5376, while the sum is 30.

The square root of 400276821 is about 20006.9193280725. The cubic root of 400276821 is about 736.9762300811.

The spelling of 400276821 in words is "four hundred million, two hundred seventy-six thousand, eight hundred twenty-one".