69721601 has 2 divisors, whose sum is σ = 69721602. Its totient is φ = 69721600.

The previous prime is 69721591. The next prime is 69721609. The reversal of 69721601 is 10612796.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55651600 + 14070001 = 7460^2 + 3751^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-69721601 is a prime.

It is a super-2 number, since 2×69721601² = 9722203292006402, which contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (69721609) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 34860800 + 34860801.

It is an arithmetic number, because the mean of its divisors is an integer number (34860801).

Almost surely, 2^69721601 is an apocalyptic number.

It is an amenable number.

69721601 is a deficient number, since it is larger than the sum of its proper divisors (1).

69721601 is an equidigital number, since it uses as much as digits as its factorization.

69721601 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 4536, while the sum is 32.

The square root of 69721601 is about 8349.9461674911. The cubic root of 69721601 is about 411.5814413407.

The spelling of 69721601 in words is "sixty-nine million, seven hundred twenty-one thousand, six hundred one".