811520670 has 48 divisors (see below), whose sum is σ = 2068978608. Its totient is φ = 203673600.

The previous prime is 811520657. The next prime is 811520681. The reversal of 811520670 is 76025118.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 38131 + ... + 55470.

It is an arithmetic number, because the mean of its divisors is an integer number (43103721).

Almost surely, 2^811520670 is an apocalyptic number.

811520670 is an abundant number, since it is smaller than the sum of its proper divisors (1257457938).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

811520670 is a wasteful number, since it uses less digits than its factorization.

811520670 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 93645 (or 93628 counting only the distinct ones).

The product of its (nonzero) digits is 3360, while the sum is 30.

The square root of 811520670 is about 28487.2018632929. The cubic root of 811520670 is about 932.7527297404.

Adding to 811520670 its reverse (76025118), we get a palindrome (887545788).

The spelling of 811520670 in words is "eight hundred eleven million, five hundred twenty thousand, six hundred seventy".