161622997 has 4 divisors (see below), whose sum is σ = 162111616. Its totient is φ = 161134380.

The previous prime is 161622983. The next prime is 161623009. The reversal of 161622997 is 799226161.

It is a happy number.

161622997 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 161622997 - 2⁷ = 161622869 is a prime.

It is a super-2 number, since 2×161622997² = 52243986318524018, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (161622907) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 243813 + ... + 244474.

It is an arithmetic number, because the mean of its divisors is an integer number (40527904).

Almost surely, 2^161622997 is an apocalyptic number.

It is an amenable number.

161622997 is a deficient number, since it is larger than the sum of its proper divisors (488619).

161622997 is an equidigital number, since it uses as much as digits as its factorization.

161622997 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 488618.

The product of its digits is 81648, while the sum is 43.

The square root of 161622997 is about 12713.1033583465. The cubic root of 161622997 is about 544.7129728978.

The spelling of 161622997 in words is "one hundred sixty-one million, six hundred twenty-two thousand, nine hundred ninety-seven".