400864787 has 4 divisors (see below), whose sum is σ = 401267856. Its totient is φ = 400461720.

The previous prime is 400864781. The next prime is 400864799. The reversal of 400864787 is 787468004.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 400864787 - 2¹⁶ = 400799251 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (400864781) 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, 200039 + ... + 202032.

It is an arithmetic number, because the mean of its divisors is an integer number (100316964).

Almost surely, 2^400864787 is an apocalyptic number.

400864787 is a deficient number, since it is larger than the sum of its proper divisors (403069).

400864787 is an equidigital number, since it uses as much as digits as its factorization.

400864787 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 403068.

The product of its (nonzero) digits is 301056, while the sum is 44.

The square root of 400864787 is about 20021.6080023559. The cubic root of 400864787 is about 737.3369012884.

The spelling of 400864787 in words is "four hundred million, eight hundred sixty-four thousand, seven hundred eighty-seven".