1661665070 has 32 divisors (see below), whose sum is σ = 3238915680. Its totient is φ = 610139520.

The previous prime is 1661665001. The next prime is 1661665087. The reversal of 1661665070 is 705661661.

It is a super-2 number, since 2×1661665070² = 5522261609716209800, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11780 + ... + 58839.

It is an arithmetic number, because the mean of its divisors is an integer number (101216115).

Almost surely, 2^1661665070 is an apocalyptic number.

1661665070 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1661665070 is a deficient number, since it is larger than the sum of its proper divisors (1577250610).

1661665070 is a wasteful number, since it uses less digits than its factorization.

1661665070 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70820.

The product of its (nonzero) digits is 45360, while the sum is 38.

The square root of 1661665070 is about 40763.5262213661. The cubic root of 1661665070 is about 1184.4439034133.

The spelling of 1661665070 in words is "one billion, six hundred sixty-one million, six hundred sixty-five thousand, seventy".