870249781 has 16 divisors (see below), whose sum is σ = 938336256. Its totient is φ = 805066416.

The previous prime is 870249767. The next prime is 870249811. The reversal of 870249781 is 187942078.

It is a cyclic number.

It is not a de Polignac number, because 870249781 - 2⁵ = 870249749 is a prime.

It is a super-2 number, since 2×870249781² = 1514669362661095922, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (870249181) 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, 97596 + ... + 106138.

It is an arithmetic number, because the mean of its divisors is an integer number (58646016).

Almost surely, 2^870249781 is an apocalyptic number.

It is an amenable number.

870249781 is a deficient number, since it is larger than the sum of its proper divisors (68086475).

870249781 is a wasteful number, since it uses less digits than its factorization.

870249781 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8712.

The product of its (nonzero) digits is 225792, while the sum is 46.

The square root of 870249781 is about 29499.9962881354. The cubic root of 870249781 is about 954.7316227310.

The spelling of 870249781 in words is "eight hundred seventy million, two hundred forty-nine thousand, seven hundred eighty-one".