61636421 has 8 divisors (see below), whose sum is σ = 76845504. Its totient is φ = 48028320.

The previous prime is 61636409. The next prime is 61636423. The reversal of 61636421 is 12463616.

It is a happy number.

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 61636421 - 2⁶ = 61636357 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61636423) 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, 400160 + ... + 400313.

It is an arithmetic number, because the mean of its divisors is an integer number (9605688).

Almost surely, 2^61636421 is an apocalyptic number.

It is an amenable number.

61636421 is a deficient number, since it is larger than the sum of its proper divisors (15209083).

61636421 is a wasteful number, since it uses less digits than its factorization.

61636421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 800491.

The product of its digits is 5184, while the sum is 29.

The square root of 61636421 is about 7850.8866378263. The cubic root of 61636421 is about 395.0139844432.

The spelling of 61636421 in words is "sixty-one million, six hundred thirty-six thousand, four hundred twenty-one".