861551070 has 32 divisors (see below), whose sum is σ = 2134425600. Its totient is φ = 222335520.

The previous prime is 861551069. The next prime is 861551071. The reversal of 861551070 is 70155168.

It is an interprime number because it is at equal distance from previous prime (861551069) and next prime (861551071).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (861551071) 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, 462270 + ... + 464129.

It is an arithmetic number, because the mean of its divisors is an integer number (66700800).

Almost surely, 2^861551070 is an apocalyptic number.

861551070 is an abundant number, since it is smaller than the sum of its proper divisors (1272874530).

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

861551070 is a wasteful number, since it uses less digits than its factorization.

861551070 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 926440.

The product of its (nonzero) digits is 8400, while the sum is 33.

The square root of 861551070 is about 29352.1902078874. The cubic root of 861551070 is about 951.5399106455.

It can be divided in two parts, 8615 and 51070, that added together give a triangular number (59685 = T₃₄₅).

The spelling of 861551070 in words is "eight hundred sixty-one million, five hundred fifty-one thousand, seventy".