161621400211351 has 4 divisors (see below), whose sum is σ = 171128541400272. Its totient is φ = 152114259022432.

The previous prime is 161621400211319. The next prime is 161621400211361. The reversal of 161621400211351 is 153112004126161.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 161621400211351 - 2⁵ = 161621400211319 is a prime.

It is a super-2 number, since 2×161621400211351² (a number of 29 digits) 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 (161621400211361) 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, 4753570594435 + ... + 4753570594468.

It is an arithmetic number, because the mean of its divisors is an integer number (42782135350068).

Almost surely, 2^{161621400211351} is an apocalyptic number.

161621400211351 is a deficient number, since it is larger than the sum of its proper divisors (9507141188921).

161621400211351 is an equidigital number, since it uses as much as digits as its factorization.

161621400211351 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9507141188920.

The product of its (nonzero) digits is 8640, while the sum is 34.

The spelling of 161621400211351 in words is "one hundred sixty-one trillion, six hundred twenty-one billion, four hundred million, two hundred eleven thousand, three hundred fifty-one".