397653551 has 4 divisors (see below), whose sum is σ = 406901352. Its totient is φ = 388405752.

The previous prime is 397653521. The next prime is 397653577. The reversal of 397653551 is 155356793.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 155356793 = 7411 ⋅20963.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-397653551 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (397653521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4623836 + ... + 4623921.

It is an arithmetic number, because the mean of its divisors is an integer number (101725338).

Almost surely, 2^397653551 is an apocalyptic number.

397653551 is a deficient number, since it is larger than the sum of its proper divisors (9247801).

397653551 is an equidigital number, since it uses as much as digits as its factorization.

397653551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9247800.

The product of its digits is 425250, while the sum is 44.

The square root of 397653551 is about 19941.2524932613. The cubic root of 397653551 is about 735.3627413365.

The spelling of 397653551 in words is "three hundred ninety-seven million, six hundred fifty-three thousand, five hundred fifty-one".