61978454 has 4 divisors (see below), whose sum is σ = 92967684. Its totient is φ = 30989226.

The previous prime is 61978453. The next prime is 61978463. The reversal of 61978454 is 45487916.

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

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (61978453) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15494612 + ... + 15494615.

It is an arithmetic number, because the mean of its divisors is an integer number (23241921).

Almost surely, 2^61978454 is an apocalyptic number.

61978454 is a deficient number, since it is larger than the sum of its proper divisors (30989230).

61978454 is a wasteful number, since it uses less digits than its factorization.

61978454 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 30989229.

The product of its digits is 241920, while the sum is 44.

The square root of 61978454 is about 7872.6395827575. The cubic root of 61978454 is about 395.7433079504.

The spelling of 61978454 in words is "sixty-one million, nine hundred seventy-eight thousand, four hundred fifty-four".