1091670372 has 90 divisors (see below), whose sum is σ = 3090409938. Its totient is φ = 335881728.

The previous prime is 1091670361. The next prime is 1091670379. The reversal of 1091670372 is 2730761901.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 32558436 + 1059111936 = 5706^2 + 32544^2 .

It is a super-2 number, since 2×1091670372² = 2383488402205236768, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is not an unprimeable number, because it can be changed into a prime (1091670379) by changing a digit.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 44788 + ... + 64724.

Almost surely, 2^1091670372 is an apocalyptic number.

1091670372 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1091670372, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1545204969).

1091670372 is an abundant number, since it is smaller than the sum of its proper divisors (1998739566).

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

1091670372 is a wasteful number, since it uses less digits than its factorization.

1091670372 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19979 (or 19955 counting only the distinct ones).

The product of its (nonzero) digits is 15876, while the sum is 36.

The square root of 1091670372 is about 33040.4354087533. The cubic root of 1091670372 is about 1029.6679018579.

The spelling of 1091670372 in words is "one billion, ninety-one million, six hundred seventy thousand, three hundred seventy-two".