70001661 has 8 divisors (see below), whose sum is σ = 93418560. Its totient is φ = 46626272.

The previous prime is 70001629. The next prime is 70001677. The reversal of 70001661 is 16610007.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 70001661 - 2⁵ = 70001629 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (70001611) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6201 + ... + 13358.

It is an arithmetic number, because the mean of its divisors is an integer number (11677320).

Almost surely, 2^70001661 is an apocalyptic number.

It is an amenable number.

70001661 is a deficient number, since it is larger than the sum of its proper divisors (23416899).

70001661 is a wasteful number, since it uses less digits than its factorization.

70001661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20755.

The product of its (nonzero) digits is 252, while the sum is 21.

The square root of 70001661 is about 8366.6995284879. The cubic root of 70001661 is about 412.1317896955.

Adding to 70001661 its reverse (16610007), we get a palindrome (86611668).

The spelling of 70001661 in words is "seventy million, one thousand, six hundred sixty-one".