816261887 has 8 divisors (see below), whose sum is σ = 942488736. Its totient is φ = 692439552.

The previous prime is 816261877. The next prime is 816261889. The reversal of 816261887 is 788162618.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 816261887 - 2¹⁴ = 816245503 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (816261889) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 600398 + ... + 601755.

It is an arithmetic number, because the mean of its divisors is an integer number (117811092).

Almost surely, 2^816261887 is an apocalyptic number.

816261887 is a deficient number, since it is larger than the sum of its proper divisors (126226849).

816261887 is a wasteful number, since it uses less digits than its factorization.

816261887 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1202257.

The product of its digits is 258048, while the sum is 47.

The square root of 816261887 is about 28570.2972858177. The cubic root of 816261887 is about 934.5657041085.

The spelling of 816261887 in words is "eight hundred sixteen million, two hundred sixty-one thousand, eight hundred eighty-seven".