1015661640 has 64 divisors (see below), whose sum is σ = 3482271360. Its totient is φ = 232151040.

The previous prime is 1015661627. The next prime is 1015661641. The reversal of 1015661640 is 461665101.

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

It is a junction number, because it is equal to n+sod(n) for n = 1015661598 and 1015661607.

It is not an unprimeable number, because it can be changed into a prime (1015661641) 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, 603721 + ... + 605400.

It is an arithmetic number, because the mean of its divisors is an integer number (54410490).

Almost surely, 2^1015661640 is an apocalyptic number.

1015661640 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1015661640 is an abundant number, since it is smaller than the sum of its proper divisors (2466609720).

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

1015661640 is a wasteful number, since it uses less digits than its factorization.

1015661640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1209142 (or 1209138 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 30.

The square root of 1015661640 is about 31869.4468103856. The cubic root of 1015661640 is about 1005.1935272469.

The spelling of 1015661640 in words is "one billion, fifteen million, six hundred sixty-one thousand, six hundred forty".